To really solve your problem, you have to ask yourself
why you're fsmashing in neutral in the first place. If you can't determine an alternative of what you should do, maybe you
shouldn't be do "anything" at all! Or just not throwing out laggy moves that are laggy and miss, which leave you vulnerable to DEATH because you're IN LAG!!! (a.k.a. Also consider why fsmash is bad, and then do things that are less bad, or good
)
So let's do something less laggy. :D (almost everyting Marth can do is less laggy that randy f smashes)
So back to the
Why: Where was the opponents when you decided to go full-committal? Grounded or in the air? Moving in what direction? Are they in lag from a rolling, missing or move, etc.?
-If they're flying at you with a move that you can outrange, fsmash is a bad choice because the endlag will keep you from comboing. You can shorthop aerial, tilt, spododge to grab, dashdance out of the way and grab, among other things. Using your movement.
-If you're tech-chasing, trying to make a read by fsmashing is a bad risk because if guess incorrectly, you completely lose your punish. Do faster things like trying to land and aerial or a dtilt to cover tech in place or one direction, and then you can pursue if they chose a different because those attacks hardly leave you in endlag. You can also wait or dashdance and react to techs, but unless your fsmash will kill them or lead you into an edgeguard, don't do it. Plus, like mentioned in the previous point, you give up the potential for combos if you just hit them with an fsmash. Landing a grab or a less laggy attack allot you much more combo potential, and therefore a better punish. If you can connect with an fsmash in nuetral, you can usually connect one of those better, safer options instead.
-Watch good Marths. If they aren't fsmashing in neutral yet succeeding, look at what they do!
The basic concept, like AirFair was getting at, is that Marth's neutral is a lot of dashdances, dtilts, wavedashing, grabs, and sometimes rising Fair. Marth's superior movement is probably his greatest asset. Superior range is great too, but is hitboxes are often brief and leave in vulnerable (especially when airborne and not combing people), meaning you have to be wise about when you choose to swing. PPMD has a fantastic neutral game, so can take a lot of ideas from him and practice them.
-Fsmash is a big commitment that you don't have to make, especially when the reward at low %s is often not even worth the risk. Until you've gained an understanding of the game and/or your opponent where you feel you can wisely position and time good forward smashes, I'd advise not using them. Especially right now, when you're breaking the habit.
I think post this is a little sloppier and lengthy than I intended, but it's something. Ganbatte, amigo.
they all say to stop forward smashing so much. This really isn't too helpful
LIES
NO JOHNS