Leather is awesome! Especially vegetable tanned leather. It's been in use for centuries, millennia, eons even. (Are millennia and eons the same thing?)
I know you all love that leather smell when you go in to Wilson's leather. It's half the reason to go in there. Unless you are a vegan. In that case you're probably not reading this. If you eat meat or are thinking of converting keep reading.

I love making bags and briefcases out of leather. It's such a beautiful, renewable resource. Granted, large unrestricted tanneries can produce some bad chemicals, vegetable tanned leather, if properly processed, limits these. Another cool thing about leather is that if you really take care of it, it will last. And it looks great as it ages. But it is also biodegradable. So when you are old and you and your leather bag are all worn out, you can just toss it and it will decompose. Can't say that about synthetic leather or any other man made products that you might use to make a briefcase. You can even recycle the hardware too!

Here I'll show you the construction of one of my bags. This one even has a hidden compartment in the bottom!

There are a ton of little steps so follow the pics. I have most of the instructions in the captions so you can follow the construction easier.

Step 1: Tools and Material

There are the basics then there are the...not-so-basics...If you are thinking about getting into leather working, just get the basics. You might even have a lot of the tools already or you can pilfer from your dad's tool box. You also can make some of the tools out of old screwdrivers, kitchen knives and what not. If you really enjoy it then little by little you can expand your shop. A good solid workbench is essential. I have a whole room dedicated to leather working but if it's just a hobby you probably don't :)

Basics(pic 1 what's not shown)
Various grits of sand paper
Piece of canvas or duck cloth
Sponge
Dish for water
Cutting board
Sharpening stone
For a work bench put a beach towel then a piece of scrap plywood on your kitchen table to protect it from your work

Not-so basics(pics 2 and 3)
I have a bunch of tools not shown that are less essential plus a nice sewing machine Juki DNU-1541

Material
You'll need a nice piece of leather about 7-9 oz. (that's the thickness) I used about 8 sq. ft. with the waste
Lining leather

Make sure you get good quality hardware
4 - 1" Dee rings (for handle and straps)
2 - trigger snaps (to attach the shoulder strap)
1" buckle
2 Tuck catches
a bunch of rivets

Leather dye
Bee's wax
Neutral leather wax ( to finish at the end )

Step 2: Design

Get out a piece of paper and start sketching. And/or google images for the type of bag you want. Once you get an idea of the shape and style of your bag you need to determine the dimensions. You can do this by gathering together what you want to put in it and shaping the items into a rough rectangle or square or octagon (who knows?). Measure your rectangle. Then that will be your inside dimensions plus a couple of inches for wiggle room. Add the thickness of your leathers and you can do a rough pattern on to paper if you're just making one bag or on to poster board or chip board if you are making more than one. Sometimes it might take a bag or two (or four) to really refine your design.

I already designed my bag and have my patterns all figured out...so on to the next step.

Step 3: Dye, Mark, and Cut

I like to use full grain veg tanned natural leather for the briefcases I make. Saddle leather!
I use a dye that comes in a powder that you mix with water. Whatever you decide to use just strictly follow manufacturer's instructions. Mine call for wetting the leather first to allow for full absorption. Wear gloves! After it's dry I have to buff it with a cloth to take off any extra dye that stayed on the surface.

Once dry mark your pattern on to your leather with a scratch awl and then cut it out. Find the best grain pattern to use for what will be the back and top flap. Use a steel straight edge along straight lines and free-hand it on curves. Make sure your blade is perpendicular to work surface and you don't start cutting on an angle. It's easy on the straight cuts but on curves you might have a tendency to lean the blade a bit. Take your time.

Step 4: Make the Handle

There are a ton of handle styles you can make. Some are overly complicated and difficult to make them look good. So I do a combo between a simple strap handle with a piece of leather wrapped around it.

Their are a lot of small steps to this so it may seem more complicated then it is. Basically you will apply all the basic leather working techniques in making this.

The pictures have the instructions...

Step 5: Attach Handle

You need to attach all your outside pieces before you can start assembling the bag.

Step 6: Add Straps and Holders

Here you can see the attachment of the straps and the holders that keep them lined up. Make sure you leave them a little long to trim off flush later.

Step 7: Shape Sides and Bottom

Here you will have to cut grooves on the flesh side of the bottom and sides, wet and shape. Also add the dees for the shoulder strap on the sides.

Step 8: Add Reinforcements and Line

At this point you can line the back, bottom and sides of your bag. I usually wait to line the front so I can get everything fitting perfectly to add the tuck catches to close the bag. It's not necessary to line the bag if you don't want to. You can also do a cloth liner but I don't like to because it usually wears out in a year or two.

Step 9: Attach Back, Bottom and Sides

Here you just have to cement your pieces together except the front. Make sure everything is flush.

Step 10: Add Tuck Catches

I forgot to take pic's as I worked here because I was frustrated. I had been too distracted by taking pics for everything that I had glued the liner on my front piece before it was ready. I just meant that I was going to have rivets showing on the inside of the liner but It still made me mad... Anyway....The tuck catches come in two main pieces: male and female. I think you can figure it out. So attache the male parts on to the flap where they need to go making sure everything is lined up. I had to trim the liner on the inside of the flap where they go because the leather was to thick. I also hid a rivet in between the slot for the catch to really secure the straps from moving at all.

Once done with that cement liner in place

Step 11: Attach Front and Stitch

Once your liner is properly attached you can glue the front onto the sides and stitch.

Step 12: Make False Bottom

The false bottom is made of sturdy grey board or chipboard.
Measure inside of case at the bottom and subtract the thickness of your lining leather on all sides. Follow the pics. Then you need to construct a simple box with no lid that will flipped upside down. This is your false bottom. Check your fit before proceeding. Now make a trap door for your lid as you wrap in lining leather. Stash your cash!

When you are done make sure quality control takes a look to make sure that only the highest standards are met.

Step 13: Make Your Strap

Cut your strap as wide as the inside of your buckle. Mine was 1". You don't want anything wider than1 1/2" because they tend to slide off the shoulder. 48" for the long part and 16" for the billet. I like to use two rivets to attach each component for strength. Some bag companies get cheap and only use one.

Step 14: Finish!

Now all you have to do is put a finish on your bag. I sometimes use neat's foot oil, mink oil or you can just use a high quality neutral shoe wax. It's just like waxing your car. Put a small amount on to a clean lint free rag and rub it in. Let it dry for a few minutes and buff it off with another clean rag. Don't leave it on too long with out buffing because it gets to caked on.

That's it you're done!