Jim is very correct on the Go0od material vs Bad material.
Once you understand..I mean can see it before you hit it understand how a flake reacts on each blow, you need to get material that will consistantly react the same.
Obsidian...Super..but you are always gently bopping scared of breaking it...If its not a 12 inch x 1/2 thick x 3 inches wide...just hit it...maybe learn something...Reason I say a big piece like that cause then it becomes a valuable piece of material, then you have to be careful...if not then youll have many smaller pieces which you can get tons of!
Most you buy cheap are just that..cracked up, inclusioned perdernales, edwards and other flints...Eats your tools up FAST...TRUST ME....But I started with it.. and it takes a whack to realease a flake but you learn power without whailing away!
I would say buy a 55 gallon drum of BURLINGTON CHERT already heat altered to learn with. WHY??? Well it always works well, beautiful colors, and your wife will let you buy miore becuase its pretty!
Serious...around 2 bucks a pound in QUANTITY already heated. You are gonna have some of the easiest rock to work. Its smooth, predictable, and you can usually see each flake after you remove it. LInes are easy to see. Plus you will get someone spauling it out in the best possible slabs for you to work.
Take your time, get it under control, remove mass first, and if you cant get to it work the side the platforms are telling you to work and it will eventually lift the other side up to attack it too. Be patient and draw the fakes you want to remove...isolate the platforms and hit them..try and get the flake you drew off...When you can do it youll impress yourself and your friends watching. Makes ya feel good and in return youll take more pride in a possible point your making.
This is what Ive done to excell in point making, watch the greats, learn from them, mimic if you have to but strive to be the best and if you have enough determination youll be there ....still gonna take many years but the learning curve will bend your way.