I wanna become a singer/screamer..like Chester from Linkin Park...read on..?

Some kid I work with suggested I listen to one of their songs through my headphones, then get like a small tape recorder and record me singing/screaming to it, so when i playback, i just hear my voice..can anyone help me out? Is that a good thing to do? I wanna become a screamer like i said. Also, when i do attempt to sing, i kinda sound like im talking and not sounding anything like him (like in the new song "What I've Done" or "Numb"), which are the 2 songs im workin on trying to sound like. I need some help becoming like Chester. Im really determined on doing this. Help would be MUCH appreciated. Thanx.