Ok so ironically Marth is my worst match up. My spacing is terrible and I can never punish fsmash tipper (or just fsmash spam in general) on shield because I don't know how to. The only thing I have are my combos. And when I watch matches like Dr PP vs M2K it seems like they both play the same but Dr PP does amazingly better. So does anyone have like, simple guide lines or just basic tips they can give me when playing this match up? Thanks.
If you get Fsmashed, first realize did you get tippered or/and did you light shield at all? If either of those this occurred, I do not believe you can ever punish it. The shield stun+push on light shield is too great to actually have an advantage over the other Marth when they do this. Otherwise, if they fsmash your shield point blank you can grab or WD OoS -> grab it.
The one thing that annoys me is fthrow -> fsmash. Always DI the Fthrow forward away from the other marth. At the very least get the DI on the Fsmash to not die right away to it lol Otherwise, if you DI fthrow away you are not guaranteed to be combo'd back. You can shield against an fsmash or spotdodge/roll against a grab.
In general for this game you want to minimize your mistakes and maximize your punishes. Sort of hard to explain it exactly how to do this, but use that as a guide as you figure it out. Really any match-up ditto is simply having the fewer mistakes (that matter) and the better punishes.