Hard mode in Guitar hero 3

Hi, I'm having a problem on playing hard mode in Guitar Hero 3 (btw I use the guitar not the controller) I don't know if I should shift my hand or extend my pinky or my index finger....

Pinky, cause when I play guitar, I use all 4 of my fingers.

Only move the hand when you are not using the green note at all. If it is just an orange every now and again, stretch your pinky. You're going to have to get good at knowing when to use which by the end of hard and getting into expert. Hell, I still can't beat two songs on the very last set of expert songs on GH III.

well the pinky is useful but for me it's very hard to play a blue&orange chord then i shift my hand and it's so confusing o.O

Use the little tab on the yellow button to know the placement. Depending on which finger lands on it, and just how the general placement of your hand feels, you won't lose track so often, if at all.