Because of the inherrent danger within this post, I've decided to screen it from the worst of the idiots. If you want to share the knowledge, be my guest.
How to Make a Bow.
From page 88 of the Army Survival mannual fm 21-76
Breaking it down into 9 steps for ease.
1) Choose a piece of wood -- You need a dry, slightly curved piece of hard wood...or bamboo. That works too and we have a lot of that here.
2) Determine the natural curve of the stick -- Every piece of wood will have a natural curve, no matter how slight. As you construct the bow, be mindful of the curve
3) Shape the bow -- You need the bow thicker in the center. So take a knife and shave the inside curve. make sure you leave the center part thick for a handhold and so it doesn't just break. The ends need to be thinnest.
4) Cut notches to hold the bow string -- Use your knife to cut notches about 2.5 to 5 cm from each end of the bow. The notches should be in the shape of a half moon on the outside of the bow's curve
5) Select a bow string. The string can be made of rawhide, thin nylon rope, hemp cord, fishing line, strands of cotton or silk from caterpillars, ordinary twine, perhaps even vines or sinew. The string should not be stretchy, as the power comes from the wood, not the string.
6) Select sticks for arrows -- Arrows should be formed from the straightest sticks you can find. The wood should be dry and dead. Each arrow should be about half as long as the bow, or as long at the bow can draw back
7) Shape the arrows -- You will need to whittle the wood smooth around the circumference of the arrow. You can straighten an arrow by gently heating the shaft over hot coals--do not scorch or burn the wood--and then holding the arrow straight while the wood cools. Carve a small notch at the back end of each arrow to accommodate the bow string.
8) Construct the arrowheads -- The simplest arrowhead is simply a carved point on the front of the arrow shaft. (You can also use bone, glass, stone, or metal, just notch the top and use string or vine to tie the tips on)
9) Make fletchings (optional) While fletching improves the arrow's flight, it is not necessary for a field-expedient weapon. If wanted, split back of the arrow, slide the feather in, and tightly wrap a thin thread.
Happy hunting.