Is there any thread around here that DOES go really in-depth in regards to Sheik's needle game?
charge your needles when you have the time
double jump and release all your needles when someone is recovering from below the stage
don't be afraid to jump out, needle, then jump/up+B back to the ledge
when someone rolls, hit them with needles if you have them
if someone is recovering towards the stage horizontally, hit them with a single needle over and over again until their staggaring recovery gets you close enough to jump off and fair them or bair them from the ledge
if you have double jumped over someone and are worried about being juggled, release your needles on the enemy below you and follow up with a d-smash, grab, tilt, jab, or dash attack depending on your preference and situation
While it may seem cool to needle cancel a lot, it doesn't make you invincible so don't spam needle canceling; it is a trick, use it like one
If a Jiggs missed a rest, don't throw needles and expect the needle cancel to remove the lag, allowing you to grab + fair. This will work against bad Jiggs, but good Jiggs can, and do, buffer rolls and spot dodges to get out of that.
If you are worried about someone approaching with a grab or dash attack and they are mixing it up very well, you may want to throw in short hopping in place with charge needles. It totally ***** any ground attack and is much easier than shielding what ends up being a grab or wavedashing backwards only to be hit by their dash attack. Hitting them with a full batch of needles also gives you plenty of time to hit the ground and then follow it up with a dash-cancelled grab.
There, I just saved you a lot of trouble.