I looked online for at least 10 minutes and couldn't find what layout is preferred for a fightpad. My friend just got the game and a fightpad, so I want to make sure he tries using the basic layout first rather than adjusting to a strange layout, being a beginner. 
 
L  M  H 
S A1 A2      That's the layout I feel most comfortable with using a stick, and is the standard, however with the fightpad having triggers, I really don't know. 
 
I'm looking forward to responses, as I'm still in shock that Google couldn't figure this one out for me.

That seems right for a fightpad, actually. 
as for the triggers, its really up to player preference 

Let your friend play around with the layout and let him choose what he feels is most comfortable.

For my stick and fightpad, I use the opposite. 
S A1 A2 
L M H    
With the triggers as the other two. I love having the bumpers. Mind you, I grew up playing MK on my sega genesis/

A1A2 
LMHS

L M A1 
S H A2 
Its just easier for me to link the attacks when they're arranged in a diamond shape rather than a straight-line because of the way I press the buttons. Its the reason why I choose a pad over a stick.

When I used a fightpad for this, I used this setup.
 
A1      A2
L    M   H
S LMH L
 
It allows easy dashing/push blocking, X factoring, and using different versions of supers for characters that have those (like Taskmaster) since it gives easy access to every combination of buttons.

Actually, tried