you hammer on on the 2nd fret (don't let go of the chord) then you use another finger and place that on the 4th fret and then let go (That's what the p2 part stands for). You only strum the guitar once at the beginning of the 2h4p2. Hope this helps.
Boooo i thought he was gona play areal guitar, i was thinking of getting this game it looks soo good. Yes that helps alot, thanks alot