#1
I have two questions on tapping-

1) What part of my finger should I tap with because I grow my fingernails out to finger pick?

2) When tapping, should I put my thumb behind the fretboard or not?
#2
I usually use my index finger or my middle finger on my right hand (im a righty) or if i want a different type of tapping i use my pick. try both the finger and the pick see which one you like more. oh and i do keep my thumb behind the neck. a fun song to try tapping with is Oroborous or Oroboros i forgot how exactly its spelled but it's by Gojira.
#3
1. Finger sounds better, imo. Don't use your nail - use your middle finger pad and build up a callus. Also, I've been told by several experienced fingerpickers that it's best to use your finger pads, not the nail, especially when you have full calluses.

2. It depends - if you're moving your left hand a lot, hold the guitar in a classical hold. If you aren't gonna move your hand around a lot, hold it however is comfortable.
#5
Wow, hey I never tried putting my thumb behind the fretboard.

I learned something today.

But I know Van Halen uses his index, and Zakk Wylde and just about everyone else uses their meatier middle finger.

I usually bring my guitar in towards me and use my wrist to power the tapping. I try not to hit my nails on the string, as it will deaden its ring.
GTFO my sig
#6
when you tap you have to through the notes away so tap and pull away from you (if that makes sense)
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