I expect there you are two reasons you have joined me today and the foremost of these will be curiosity.
Having been hanging around fanfiction in general for some time I know a couple of you will be thinking 'What does this smug person have to say and what do they have to offer. Why are they so good to be telling me how to run my fic! It my writing and its only fanfiction so I can do whatever I want, ect, ect.
Whoa mate, carry on soldier! This is just me offering the advise I have to give after, ooh, must be a decade now of writing fanfiction.
Consider this part as quality control and an easy checklist to take before each post. By ensuring you've done these things, the very, very least you can do to make your fic the best it can be, it shows you have pride in your work and it quickly wins the respect of a reviewer. By getting these things right it means the reviewer doesn't waste time on the basics and can direct attention and compliments to where they deserve.
These are also the small things, if you can't take the time to get the small things right, its unlikely your going to take the time to get the big things right. By not at least attempting these things, what is shows to the reader is laziness. If they don't care about their fanfiction, why should I?
Bye bye reader, and don't you want every review you can get your hands on?
The good part is that once you know about these things, they'll become second nature so you don't even have to think about them, promise! Think of this as the start of a wonderful hobby and a wonderful source of fun and happiness.
In this section I should also warn you, I've never taken more than high school English. These are just thetidbits I've picked up through copious reading of published and fan fiction. I should also mention that my interests lie mostly in OC fanfictions so that's where my examples will come from and tutorials will be directed towards, but I think what you find here will go across the board.
Get in, get around, review, rewrite, talk to fellow authors and get the basics right!