I always use liquid eyeliner; mine is a no smudge one, so never does. XD I like my eyeliner thick so it's probably easier to get the line straight than if you're doing a subtle line.
I have a pot and a brush that I love to use. You have to have a steady hand for it though. I use it when I'm doing dramatic stuff.
I love those little twisty eye liners too. The pencil ones, except they twist? I use those when I want a thin line.
And then I use a normal pencil for when I do smokey eyes. They seem to smudge better.
Liquid..I use that sparingly and never in black. Because I always seem to blink and it ALWAYS gets on my upper eye. Oh, it's so annoying.
I hate water proof anything. It's so freaking hard to get off! Even with make-up remover! It's just a pain in the butt.
If I treated you bad, you'd bruise my face. Couldn't love you more you got a beautiful taste. Don't let the days go by...glycerine.
Ah, but mine is smudge proof, not water proof; so it's easy to get off afterwards. ^^
You must always remove eyeliner and all eye makeup before you go to bed; it will come off on your pillow and make your eyes puffy next morning if you don't!
I only put my pencil eyeliner in my waterline and it gives a natural look. If I want to be daring I put a thin line of liquid eyeliner on the top lids.