Emo Eyeliner

Eyeliner
Apply cover, blush, or powder first as these products not only make application of eyeliner easier but also help it to stay.
Draw a line on your upper lids, from the center to the outer portion, narrow to wider.
Finally draw a line on the lower lids using the same technique above.

(This is how I do mine)
Take your eye paint or eyeliner and apply it carefully on the bottom of your eyes. Make sure you get close to the lash line. Start on the inside corner of your eye and make a thin line going to the outside of your eye.Then add more black over the top, keep adding black till you cannot see anything more! This gives it a dark emo effect.
Apply your eye paint/eyeliner in the same manner on top. Try for a rounded edge on the outside corner of your eye.
Apply a healthy amount of eye shadow to your eyelids after the eyeliner has dried.
Apply two coats of black mascara.
Use foundation in a tone slightly lighter than your skin tone, or your own skin tone.
Put a tiny bit of lipstick on. Blend it well into your lips and blot some off for a tinting effect. Or you can just smooth on some foundation along with powder to add that pale lip effect.

Do your make up as bold as possible. Applying a striking amount of eye-liner is standard in the Emo scene. Do not apply this kind of make up to go to work, or if you're school does not allow such things, or you'll find yourself in trouble. If there's a potential for smudging, then try using eye pencil instead of liquid eyeliner.
The Emo look usually includes being as pale as your natural skin tone will allow. Keep your skin pale and use suncreen to make sure you don't end up with an ultra tanned, sun kissed look which will take you very far from looking Emo. Also, the clearer and paler the skin, the more striking your makeup will look. You can also get a whitening foundation. This isn't extremely important so don't go overboard with this - you don't want to look like a clown.
Dark nail polish is recommended. Black is normal, but other colors such as dark green, dark purple, or even black and white stripes could work. Make sure your nail polish doesn't chip or wear out, or it'll start to look cheap. But also bright colors will work, whatever you feel like doing at the time.

Quick note: If you have a very light skin complexion and maybe even darker eyes, you may want to use like a dark brown (close to black) and/ or a crimson color. This will not be to harsh on your skin tone!