It depends on how good your friend is, but other than that, snadmonkey and heroes got you covered.
What I do sometimes when people are on the edge is to jump above the edge and neutral A, that way if they do anything except roll back onto the stage, they get caught in its multiple hits.
Makes it where I don't have to focus so much on timing, and if they stage attack, it misses me. Just, you're left to your second jump to recover (and if they're at the right distance on your jump back to the stage, bair them or uair them: no landing lag.)