Platform cancelling can be done in lots of ways.
Basically pressing down on the control stick as you're going above a platform is the simplest way, down on the c-stick also works as c-stick is just direction+a, but there are a few characters you don't want to use the c-stick for. (Pikachu comes to mind as his dair doesn't auto-cancel on the first frame)
If you hold down and press A as you're going through it also works, same with holding down and pressing c-stick in any direction.
If you hold down and press B as you're going through you'll platform cancel, but the b move may come out anyway. (for example if diddy platform cancels in this way he'll platform cancel and down-b instantly)
I'm not sure if you can hold down and press shield to platform cancel, someone else should confirm that.
Platform cancelling can be done on any moving platform, the most obvious examples are Smashville and Lylat. Smashville's platform is pretty much always moving, and Lylat's platforms while they may not look like they're moving, are always considered moving excluding when the ship is travelling between different areas or backgrounds. It's interesting to note that character's with multiple double jumps can't platform cancel during a double jump.
The timing is hard to get down at first but after practising it lots it should become clearer.
Basically pressing down on the control stick as you're going above a platform is the simplest way, down on the c-stick also works as c-stick is just direction+a, but there are a few characters you don't want to use the c-stick for. (Pikachu comes to mind as his dair doesn't auto-cancel on the first frame)
If you hold down and press A as you're going through it also works, same with holding down and pressing c-stick in any direction.
If you hold down and press B as you're going through you'll platform cancel, but the b move may come out anyway. (for example if diddy platform cancels in this way he'll platform cancel and down-b instantly)
I'm not sure if you can hold down and press shield to platform cancel, someone else should confirm that.
Platform cancelling can be done on any moving platform, the most obvious examples are Smashville and Lylat. Smashville's platform is pretty much always moving, and Lylat's platforms while they may not look like they're moving, are always considered moving excluding when the ship is travelling between different areas or backgrounds. It's interesting to note that character's with multiple double jumps can't platform cancel during a double jump.
The timing is hard to get down at first but after practising it lots it should become clearer.