I don't play fighting games too often, so take this advice as you will.
>content to featurePeople come to YouTube for entertainment more often than information. Of course, people do both though, it brings in a larger audience.
Content to feature is often along the lines of highlights and short clips or funny/weird shit that's happened. Everyone loves that. Easy to clickbait, short enough for people to watch, and people might investigate your channel because of shit like it. If you introduce with some funny stuff on the front of your channel, I know I would be a sheep and stick around for a while.
>good start to upload matches?Of games? Eh, maybe. I mean, there's more than enough of them on the internet as it is, but it's a good way to get a feel for what your doing. If you do, use them as an exercise instead of an attempt for traction. If you're super good at what you do, though, then you should feature the matches to make people think "Hey, that's pretty good!" or some shit like that.
If you're just "competent" and not a high tier player who could compete with whoever is at the top or w/e (idfk mate, i play shitty games like tf2 not tekken 2) then upload some, yeah, but use them to be able to give better commentary in the future and make it good practice.
>participating in online communities and join their streamsName one good website for this. Fucking one. That's right, they don't exist. Try Twitch streaming if you want, though. That might draw in a few viewers if you do it for long enough. Make a website instead or something.
>worthwhile shitAnything that suits the following:
>funny>interesting>weird>helpful>TOP TEN LISTS (not even fucking kidding, do those)Remember to not go overboard and tire yourself with work on videos. This is a bad habit.
Enjoy yourself, and remember the one anon who can't get any fame. If you want to check my terrible fucking crap out, here you are:
https://www.youtube.com/channel/UCkfLtL9CTUNXyvpYBPK5oew 
