I've never really played particularly heavy stuff, so it wasn't until this year that I started trying to do pinch harmonics. From what I gather you're supposed to tap the string with the tip of your thumb just after you pick a note to get that squealing sound . . . for me, this has turned out to be impossible. My thumb always hits the string too hard and it mutes the string.
I'm able to get them about 80% of the time that I try by picking and almost simultaneously sliding the top of my right hand index finger nail into and past the string. (It's like the pick hits and then almost simultaneously the nail hits the string) Is this just really bad technique, or have I discovered an alternate way to do them?