I will explain how to make this small bookshelf, but I forgot to take pics.
Step 1: The Big Three
You need scissors, duct tape, and (last but definitely not least) sticks with decent thickness. I just walked around my yard and gathered some. (I also found a dead baby bird :'(...My dog tried to eat it)
Step 2: Clean Sticks
Peel of bark (if you can) and clean with a wet wash rag.
Step 3: Getting Sticks Ready
Take a group of six medium sized sticks and two larger ones. (look at pic for details) Take the six medium sticks and snap them to about the same size. Discard the snapped pieces. Tightly duct tape the same sized medium pieces in groups of three. Only duct tape ONE side on each. Now do the same to the large pieces but do NOT tape any part of them.
Step 4: Assembly
Take the large sticks and slide them down the three medium ones. Have a stick in the middle and one on both outer sides. Have the front large one a little higher than the other one. duct tape the outside, inside, and above. Do the same with the other side. Look at the pic for details on where to tape.
-Color Code For Pic-
Step 5: Adding Strap
Cut a desired length of duct tape and fold in half. Fold any excess sticky sides over. Now duct tape it to the top. Voila! Homemade Bookshelf! You just have to screw it in the wall. Make sure to screw THROUGH the strap.