What are tips for playing Guitar Hero in hard mode?

"use 3 fingers and go on practice mode" I suggest using all four fingers, try keeping your hand on the Red, Yellow, Blue, Orange. I'm assuming you aren't having rhythm troubles with hard, only the orange button throwing you off. Using your four fingers on RYBO keeps your pinky on the orange, which is often easier since you won't have to stretch it. Stretch your index finger for Greens. Once you get the hold of the Orange button, try moving your hand to your leisure on the buttons. If you are having rhythm troubles, just keep working at it. Good luck!