for fsmash:
Run
Pivot
Press and hold original direction on C-Stick
Press and hold Z to charge.
With dsmash I use Z to charge as well.
Chok: Hydrograb is a grab that slides the same distance as hydroplaned moves. Unlike the others it always seems to move at max speed. Unfortunately the grab range isn't increased past the standard animation length, but the effect is that you can grab somebody in the middle of final destination and still dthrow them from the edge. It greatly increases squirtles kill potential.
It's also slightly easier and safer because a) you use the pivot as a means of baiting a missed attack and b) if you miss you often slide past them very quickly.