Not all are DIY -- some involve products to buy which will save you money in the long run -- but I've only included those if they really save you a lot, and might even change your life like the next step changed mine....
Step 1: Selzer!
I'd thought of building some sort of seltzer making set-up, and found a few descriptions of how to do it, but they all seemed too involved, (and dangerous) to be practical for me. Then I found the soda club, and it did, literally, change my life. In a way it is DIY because I now make the selzer... I don't need to carry the weight or pay for the water. I use tap water (transported via the force of gravity) and just pay for the bubbles -- about 20 cts per liter. Not only do I save a whole lot, but I don't have to carry the water and I never run out! Safe, easy, cheap. What more can you ask for?
Step 2: Renovation
Reuse. When I tore down the bathroom walls I saved the old tiles and used them as a backsplash in the kitchen. I also saved the accessories (toilet paper holder, etc) and put them into the new wall.
Give away. When I tore out the kitchen cabinets, even though they weren't so great I found somebody who would take them for free. I found a scrap metal guy who picked up the huge old bathtub. Not only were these people glad to have the stuff, I saved hundreds of dollars the contractor would have charged to cart them away...
Find free stuff. There's the aforementioned dumpster diving, online resources such as Craigslist, but if you make friends with your architect and contractor (or if your friends and family happen to be architects and contractors), ask them for stuff they're tearing out of their other projects. I got a free stove, dishwasher and a butcherblock countertop (in addition to smaller things like door hinges, handles, mirror, light fixtures, doorbell, etc).
And of course, do as much as you can yourself... but beware of false savings! It would have cost me more to rent the floor sanding equipment and supplies than it cost to pay someone else to do the job (better and faster, too). That might be because I would also have had to rent a car to get the equipment. Still, figure in all your costs before you decide to do everything yourself.
Step 3: Hope
Put your power warts onto a power strip and turn them off when you don't need them!
Step 6: Excercise
Step 7: Weddings
I used to edit wedding videos -- what some people spend on weddings could buy them a house! I know first hand because I was living off of them...
You might think now it's what you've always dreamed of, but in less than a year you'll be shelving all those pictures, the video, and you'll never think of that extravaganza again (unless you're still paying off the debt). It's not worth it.
Step 8: Washing
I also make my own cleaning products. It's quick, easy, cheap and green!
I'll be testing my own high borax mix for h.e. washers and I'll publish that when it's ready....
Update: don't try the high borax mix! In high concentration, borax will form crystals -- you don't want those clogging up your washing machine pipes.
Step 9: Drying
Joyful Spin Cycle
This can go anywhere, you don't necessarily need a laundry room... a very large closet, a hallway, the bathroom, even your bedroom. I wouldn't put it in the kitchen though, unless you never cook.
I'm sure this could also be a DIY project... after all, it's only a few pulleys, a couple bars, cable and a crank... But that last item was why I opted for the commercial solution. You could theoretically replace the crank with a cleat and pull your bars up and down, but the crank makes it much, much easier. When you're doing laundry every two or three days, it makes a difference. A bar full of wet clothes is pretty heavy. Plus by the time you've bought all the separate items, I'm not sure you'll have saved that much money...
As you can see I do still have a dryer, but it uses gas (more efficient and cheaper to run), and it's useful for sheets and towels. Hang the rest!
Step 10: Cleaning
Make rags -- cut up your old Tshirts and moisten them with warm water... that's all you'll need for dusting (trust me, I live right next to a highway so I know all about dust...).
Don't buy softener -- plain white vinegar works just as well (and it won't smell)
Forget the $10 carpet cleaner (even though I'll admit the foam is kind of fun) -- spray your carpet with water, sprinkle it with Borax (20 Mule Team is in any supermarket with the laundry supplies), wait for it to dry and vacuum. Not only will you get the dirt, you'll also kill the fleas...
Click here for some good and very cheap cleaning supply recipes.
Step 11: Learn to cut hair
Just two pieces of advice:
The fist time you cut someone's hair, choose a subject who is older than 14 (younger than that they tend to move and jump around too much), not too vain, and preferably broke. That way you'll be forgiven for any mistakes.
If you don't want to cut your own hair, don't enlist someone who appears to be nervous. I was once left with half a haircut after my improvised hairdresser panicked and refused to finish the job...
Step 12: Don't sponsor Hallmark
Step 13: Don't sponsor big pharmaceutical companies
Step 14: And also make your own toys
Check out these ideas for turning empty bottles into toys.
If you like paper craft, you can download my popup kitchen to make a very cheap and portable toy. Or go all the way and make a whole pop-up paper house, sturdy enough for real play. It also comes apart and folds flat for storage (this one isn't free, but it is a whole lot cheaper than any other fully furnished doll house you can find).
Here's another cheap toy idea: I used to play this game surreptitiously during class on notebooks or scrap paper, so I was horrified when I saw "Battleship" for sale as an expensive toy with hundreds of small plastic pieces -- all you need is a pencil and some paper, but drawing the grid can be tedious so I made this PDF file which can be downloaded and printed.
Step 15: Let there be light
Step 16: The next generation
A few years ago, when the boy in this picture was only 5 years old, he became very angry at me. He went around the apartment, turning on every single light.
"What are you doing?" I asked, trying not to sound as annoyed as I was.
"I am wasting energy!" he said, furiously. He knew that it was the best way to get back at me -- and he never guessed how much his answer had pleased me.