I usually never wear it because it always looks so sloppy because I SUCK at putting it on. Any tips on how to apply it so it looks nice?

put on pencil eyeliner first. go over it with liquid. so it's an even line. does that make sense?
eventually you will be so used to it you won't need the pencil under it.

I find, though, even when I use pencil, it's still messy just cause my hand is so unsteady. I just want a verrrrrrry thin line, too.

like this; http://www.thesaturdaypost.com/images/alm_47_s00.jpg

Well, some people just can't do it. But try doing the line in a bunch of teeny strokes starting right at your lashes and going down into them, if that makes sense. It's easier than just doing one long line, and it looks the same.

put on pencil eyeliner first. go over it with liquid. so it's an even line. does that make sense?
eventually you will be so used to it you won't need the pencil under it.

I would also recommend putting pencil and then the liquid. this helps so much!! it's like... coloring inside the lines in a coloring book. I also sometimes pull the outer edge of my eyelids to put it on so that it looks clean instead of sloppy.

practice