Items you will need for a complete snake set-up for a dry species of snake include:

An enclosure of appropriate size $70 - $300: I highly recommend an enclosure set up from zoo med since it has the security latches, a strong metal screen top, and great space for most beginner snakes. I have included a picture of the snake kit I have used several times for my snakes made by ZooMed. I don't end up using everything, and do have to get additional supplies to complete the kit, but for a beginner it is a little less overwhelming. I got this exact enclosure for around $172 from a local feeder store. I would not recommend buying this kind of enclosure online as many people report getting broken enclosures. Try instead to find a local feeder shop (rodent, insects, other feeders) instead of going to a big chain pet store as the prices are usually lower.

This kit includes:
1. ReptiTherm® Under Tank Heater
2. Aspen Snake bedding (8 qt.)
3. Habba Hut (med)
4. Plastic Bush Plant (Mexican Phyllo, med)
5. Repti Rock Water dish (med)
6. Analog Reptile Thermometer
7. Daylight Blue Reptile Heat Bulb (100 w)
8. Mini Deep Dome
9. Lamp Fixture
10. Guide to Reptile Care Booklet
11. ReptiSafe® Water Conditioner (2 oz)
The under the tank heater #1 works really well, and provides belly heat for digesting. Snakes need belly heat in order to digest well so this is a great option. The only issue is that the stickiness does not last so I have found that adding aluminum foil tape to all the sides helps to hold it in place.
The aspen bedding #2 is great for desert species of snakes, especially species that love to burrow because the aspen will hold the structure of tunnels they make... at least until a pesky human messes them up. It is also very absorbent for their waste, and safe to use with all species.
The Hubba Hut #3 is a hide that comes with the kit and works really well for dry to slightly humid enclosures. This will not work for a high humidity enclosure do to moulding issues.
Plastic fake plants #4 are great for additional hides as it makes an enclosure look more natural, helps make the snake feel safer, and is a safer product to use then anything found outside. If you do wish to get more fake plants, find fake plants with no metal wire inside as those can really harm your animal if any of the wires start to stick out or get too hot. Outdoor plants will have bacteria and may have parasites that can make you animal sick. If you wish to use outdoor plants or wood there are ways to clean/bake them so they are safe.
Repti Water Dish #5 is a good start for a water bowl, but you will want to make sure you have a large enough water bowl for your snake to completely fit in as some enjoy soaking. The texture can be harder to clean, but does provide one option for your snake to rub off shed when shedding.
I don't recommend using #6 Thermometer as a secondary addition for watching temperature because this isn't the most exact thermometer and can cause a lot of issues if you do not have a better gage added to your set up. Many keepers don't suggest even using this due to them falling off when snakes climb on them or their snakes getting stuck to the adhesive. Over time I have removed as a personal preference.
Of these supplies I DO NOT use #7, #8, and #9 because of the species of snakes I have do not require the over the top heat, a lamp takes up a lot of top room, and because the matt gives sufficient heat.
ReptiSaft Water Conditioner #10 is something you don't have to use, but I'm of the mind that it can't hurt anything to add as it has some good aspects that are healthy for a snake.

Extra Hides: Snakes do not do well if they feel out in the open too much, so having additional hides is a must. There should be one on the hot side of the enclosure, and one on the cool side of the enclosure. I like to have at least two large hides for each side, 2 to 3 fake plants, and then a thick layer of substrate that my snakes can completely bury themselves in. I have also created collage backgrounds for the back side of each of my snakes enclosures that help to limit the amount of empty space they can see out.

You can use many things as hides, toilet paper rolls, shoe boxes, handmade clay hides, etc. As long as there are no sharp edges that can harm a snake or worries that the hide may overheat too easily.
I might do another informational DIY on how I have created the collages as I use photoshop to create a little more streamlined of a design, but anyone whose creative can come up with a unique background.

Aluminum Foil Tape: As mentioned with the tank heater, the aluminum foil tape is used to keep the heating matt in place under the enclosure. I also use it in several other places of this set up as I feel comfortable using a tape that is heat resistant more than regular tape.

Century Digital Heat Mat Thermostat Controller:The specific heat mat thermostat I have bought is both a cheaper option then some of the others out there like herpistats, without being so cheap that I fear it will cause a big issue of overheating or under heating a tank. I have one for each of the four enclosures I have, all have worked wonderfully. These same thermostats have been used for my PVC set-ups and been just as successful with that set-up material.

Cleaning Supplies: There will be a need to clean a snake enclosure monthly, some snakes are messier than others though so some can go a little longer then that with constant spot cleaning.

Paper Towels
Nature's Miracle
Flukers
Trash Bags

Small Nosed Pliers: Used for wood hides

New Zealand Sphagnum Moss: Used for Humidity Boxes.

Step 1: Quick Message Before We Begin

There are lots of controversial topics when it comes to the reptile hobby, what to use in enclosure set ups, and how to interact with your reptiles.

This is just my own experience and research on how I learned to do a simplistic snake setups using the zoomed snake kit. As this is a size specific enclosure, you may need to upgrade your snake enclosure to something else later. I personally have most my snakes upgraded to a pvc enclosure after the first year or 2 of their life. This enclosure is best in the first year and helps prevent escapes while the snake is small and young. Of course some species that stay small can be comfortable in the zoomed enclosure for their full life span.

This is a continual learning process that you will be going through. Not everything is going to be something you want to do, but it gives you a starting point. Something that I had to piece together more so.

Other controversial topics for the reptile hobby are feeding in a separate enclosure/tub, housing in tubs over an enclosure, feeding live vs feeding frozen thawed, items to use in enclosures, placements of items, etc.

It's a great hobby to get into, but want to give you enough warning that there are sensitive areas of discussion. This is the result of people having strong bonds and emotions over the care of their animals. You can adapt to what you feel works for you and makes the most sense in these areas of reptile keeping.

Now let's get to the good part. Setting it all up!

Step 2: Placement

With all the items you need in hand, you can now set up your snake enclosure.

Elevating Enclosure: There are sticky dots that are included with the kit to elevate the enclosure. This is to provide proper airflow for the heat matt. These dots are harder to work with, and sometimes don't stay in place well when the sticky side is attached to the enclosure. I found that it was easier to have the sticky side attached to the surface the enclosure sat on (had to line up the enclosure four corners with the placement of sticky dots).

Alternatively, I cut up an unused sponge, and place those pieces in the four corners. When you move the enclosure to clean, I have found that it's easier to fix the sponge placement then the sticky dots.

Century Digital Heat Mat Thermostat Controller Placement:The temperature reader can be placed in two places on the enclosure. It can be placed between the bottom of the enclosure and the heat matt, or it can be snaked (pun not intended) into the enclosure above the area you attach the heat matt. There is a small spot for this wiring to get past the enclosure lid. I use aluminum foil tape as it is tape that can handle the heat from the matt. If you place the temperature reader underneath the enclosure, you limit the risk of the tape getting stuck to your snake. The reason why some place the reader in the enclosure is the accuracy increase of the reader. The layers of glass and substrate can mean a change in the temperature being read. I have shown how I would place if inside the enclosure, but I personally think that placing the reader between the heat mat and the bottom of the glass is better. This is because if the tap loosens inside the enclosure, a snake can get caught on the tape. The thermostat can be toggled to the correct temperature with some readjustments if the enclosure needs more or less heat.

Paper Tower Layer: For ease of cleaning later, I like to add a thin layer of paper towel. When I need to clean the substrate out. I roll the substrate tight, and can pull most of the substrate out. Warning is that you don't use paper towel only, and you try and place substrate around all paper towel corners. Snakes can sometimes start to accidentally ingest the paper towel with their meal, which can cause blockages. I placed a thick layer of substrate over the paper towel so it never was an issue.

Heat Matt: You will want to determine a warm side, cool side and a hot spot for your enclosure. This will allow your snake to thermal regulate. Something all snakes need to digest food correctly, and be comfortable in their enclosures. Add the heat matt by removing the sticky cover and facing the heat matt cord towards the back fo the enclosure. I add the matt under the tank on the left side (thus becoming the warm side of the enclosure) and then use aluminum foil tape to all four sides. The stickiness of the matt tends to decrease overtime, so it's good to preemptively add the tape to keep the matt secured. Always check your heat matt is secured when you clean your enclosures or if you see there is a heating issue occurring. The hot spot of the enclosure is now where the matt is placed. Set the temperature to be what keepers suggest for the hot spot of the enclosure. The other side of the enclosure will be recognized as the cool end.

Example: My Mexican Black King Snakes Hot spot should be 88 to 90 degrees fahrenheit, and should be in mid to low 70's for the cool side.

Substrate: Some species do better with one substrate over another. For desert, dry, and some burrowing species, I have found that the aspen substrate provided works amazingly well. It holds the burrow structure well, is very absorbent for waste or spilled water, and is fairly easy to clean. Other species may need more of a coconut based substrate, but this enclosure style isn't great for high humidity need species (unless you make a ton of adjustments). I add about 3 or 4 inches of substrate for my snakes as they love to burrow, and it increases hide locations. A species that may not burrow as often may need more climbable objects instead of a thick layer of substrate. I do dig out the substrate around the hides to create a sort of den area, and to get them closer to the heat matt source for the warm hide.

Hide Placement: Two hides are the minimum amount you want for your snake, one on the warm end, and one on the cool end. I usually have 3 to 5 hides with fake plants scattered around them. The wood hide shown have staples in them that you will want to remove (if possible) as this can be a danger to your snake. I use the small nose pliers to remove. As stated before, I like to move most the substrate under the hides to create more of a cave.

Other hides can be made from different items like toilet paper/paper towel rolls. Just be sure that there isn't any paint/wood chemicals or sharp edges that can harm your snake.

Water Bowl: Place on the cool side of the enclosure, and add a drop of ReptiSafe® Water Conditioner. Again make sure this bowl is large enough for your snake to soak.

Step 3: Side Notes

Some side notes to consider.

Enclosure Backgrounds: Snakes may become stressed with all four sides of the enclosure being clear glass. Snakes feel safer when they feel unseen. I would suggest added a background to 1 to 3 sides of the enclosure. As a way to bring more of a creative design, I have created collages themed around my snakes name reference. Loki and Luna's background collages examples are provided. I just took cool photos I liked, added them to 8 1/2 by 11 pages and fit them together once printed. Sizing was sometime a little off, but I was just having fun with the idea. You may come up with better ideas. I added this outside the enclosure with the design against the glass. Just be careful with artwork you take, and how you share as some may not be public domain artwork that you do not own.

Snake Behavior: Watch your snakes behavior and make adjustments to the enclosure. If you see your snake is trying to climb the enclosure (after the first week as they do have a period of roaming when first introduced), hiding directly under their water bowl, or they are spending most their time on their cool side, their temps may be too high. If your snake regurgitates a meal, you may not have a warm enough hots spot needed for digestion. Over soaking (some species are just water lovers) can mean they may have mites or may be trying to cool down. After about a week or two, they should really mellow out, and not explore as often. This of course is also dependent on the species.