I have made my own bow using multiple lengths of alder lashed together and believe it or not I used hide strips from a deer skin to lash the sticks and to make the string. The arrows are the hardest to make (getting them strait is a pain in the ass) and the arrow heads take a lot of effort. The first time I drew back the bow the string broke and I ended up punching myself in the face by accident.

Lucky for me, no one was around to see. By the third attempt I had a solid string which could place an arrow on target reasonably well all things considered.
I am an ethical hunter so I never attempted to use it on anything living out of fear of maiming the poor critter. It was fun to make all the same.
Currently I use a PSC typhoon with 60-70 lb draw, 75% let off, with a cobra 3 pin sight, quicktune 360 capture rest and a hurricane buckle fold back release. I use 125 gr broad heads and dropped a nice fat doe with it last year. It's a far cry from a home-made bow, and actually cost more than most rifles.
The technique however, does not change and much skill is needed to get to within that 30 yard range. The more I hunt with my bow, the more my guns stay locked up. It’s really starting to grow on me more and more. The meat tastes so much better when you work your arse off to get it as well.
It should be pointed out that you cannot realistically hope to take deer or other large game.
Why the heck not?