I graduated from college with twin XL sheets, an engineering degree, and a car too small to fit a mattress. After a week of sleeping on the floor (and a bit of back pain) I decided I needed an upgrade. My goal was to make the bed comfortable without a mattress, minimalist in the amount of material it used, and colorful (note the light green accent wall).
**Vote for me in the before and after contest**
Step 1: Building and Weaving the Bed
After a rough sketch of the bed, I bought three 8' long 2x4 pieces of wood and cut them into two 83", and two 49" pieces. 2x4's actually have the dimension of 1.5"x3", so this would make the inside of my bed frame the size of a twin XL bed. I cut the remaining scrap wood (plus an additional piece I found on the street) into even sections to form the legs (13" each).
I purchased some second-hand paint from Rhode Island School of Design's Second Life store (shameless advertisement: if you're nearby Providence, you should check it out, that place is awesome- they have every type of second hand hardware you can imagine!) and spray painted the pieces.
After painting, I drilled holes every three inches along each section of wood, assembled the outer frame first, and then attached the legs. If you want to try this and haven't done much woodworking, remember to pre-drill the holes for the screws first!
Weaving the bed was fairly simple- the picture is worth a thousand words here. I started with the long side and after it was done, I wove the short side up and down the existing string. It helped to attach a deconstructed paperclip to the end of the string with a piece of duct tape to make it easier to pull through the wood. At the end, I just wrapped it around the post a few times and tied it off. For the string, I chose to use clothesline, and it ended up being really comfortable and not fraying at all.
Lastly, to hold my bed sheets in place, I took some drywall plastic anchors, cut off the bottom, and drove a nail through each one. Really, I could have used anything here, but I was just looking for something that wouldn't damage my sheets and I figured this would do the trick. I put a nail on each post, and hooked my sheets around them.
...And no more back pain! I was a bit worried at first, since sagging mattresses can be bad for some people's backs. This bed probably goes down about 6 inches at the lowest point. I read up about it a bit, and hammocks can eliminate pressure points on your body, which might explain why this bed ended up being so comfortable.