its just a fact rest isnt always necessary and its true, like shiek you can pull of a combo like pound (upwards) up air, then some back airs if he DI's wrongly.
-pound to rest, try make the pound just slightly hit, its easier to rest
-u air to rest (using c stick) i find this usually good against fast fallers and marth
-f air to rest usually destroys the iceys, because nana dies, or they both do
-d air to rest..indeed stylish but prob one of the most annoying to pull off due to the lag and the way it hits
-n air to rest, you have to use a n air late in the shuffle to pull this off without it being blocked or dodged, getting used to the % push from it too can be tricky (including diff char's weights)
-up tilt to rest, you can also pull this off after back air, or f air/n air through them, usually sets up a nice rest and is a good mindgame (not to be spammed though)
-sleep to rest.. id say aggrevate your opponent into following you off the edge randomly, during a random match
-pound to b air to rest, sometimes work depending on the DI of the pound and the way it hits, and if the opponent DI's into your back air then you got a nice rest set up and usually enough % to instant kill
Great counter picks for jigglypuff is usually annoying stages like Mute City (use rollout to edgeguard, it *****) and Rainbow Cruise (so much air space and hit under platforms)
also consider spacing is very important with every char, especially jigglypuff..wrong spacing can lead to **** from fox/other chars usually by up smash moves and deadly combos. And DI is very key too, jiggz's DI can be amazing can survive to annoying %'s
Another trick thats great to learn is the smash DI trick, to do this is hold both sticks down and tech just when the move hits, this can be used to save you from up smashes or other moves at high % when you miss a rest..but this trick can also work on other chars.