jiggs is such an easy match up once u learn it
just camp with lasers, then after that shoot some more lasers, act like ur approaching and then WD back and continue to shoot lasers, next you should run away and shoot lasers
i'm not even joking, anytime jiggs is in the air you should be shooting lasers; if they get a little too close for comfort just wait for them to throw out an aerial, nair through them and continue your lasers
if you're fast and smart jiggs won't be able to get near you while lasering
once they get tired of that they'll probably start crouching on the ground, now you should either dair > shine > bair or uair (or just hit them with another laser to make them feel worthless). or you can just grab them, not enough falcos grab jigglypuffs. you can't do anything from a grab, but you're doing damage and aren't getting rested so it's win win
at higher percents you can dair to dair to jab to whateva
just be really patient and sooner or later you'll land a bair or nair that sends them all the stage, shoot lasers at them while they're off and then edge guard with bair once they get close. if they try to come in low just wait for them to do something stupid and then spike them, but never leave the stage..... if you find they will make it back no matter what you do just set yourself up to shoot more lasers
also at higher percents you can dthrow to usmash if they don't DI correctly, but they can also rest you after your dthrow..... you can take the chance if you want
edit: learn to DI the uthrow, and if you are getting shield grabbed than you are starting your aerials too high in the air; if you dair or nair low enough and cancel into shine then there is nothing jiggs can do
