How to Write in Proper Grammar & Make Your Stories Appear Fabulous

I'm getting a bit tired of this.
Don't call me a Grammar Nazi or anything, but there are some these popular stories (talking about real stories, not rants and stuff.) that have quite a bit of grammatic errors and some pretty bad word choices. So before you because these bums, read this if you don't know something about grammar or word choice.

Or y'know, just leave.

(Also, add suggestions to add how to do some of this, some of that, I hope to be able to do it correctly.)