Choosing the Right Liner
Black pencil eyeliners provide the most precision and are easy to control--when you use a pencil eyeliner you're essentially "drawing" the way you would on paper, and most of us are familiar with that motion. Pencil eyeliners are good for well-defined lines and basic eyeliner looks.
Black cream eyeliners were once nearly exclusively in the domain of professional makeup artists, but today several drugstore brands offer cream or gel liner formulations. With their richer texture, cream formulas can be "painted" on and actually used to cover the entire lid in the place of shadow. Because they blend and smudge well, black cream liners are ideal for smoky eyes or messy rock-chick looks. If you don't want any smudging or are less experienced with eyeliner, creams may not be your best choice.
Liquid liners are often used to create the retro "cat eye" look. The angled pen used to apply most liquid liners is great for flicking the line out the end and varying the width of the line over lid. Liquid eye liner has a wetter, shinier look to it even after it's dried.
Black eyeliner adds definition and brightness to the eyes.
For a natural look, lift up your eyelid and hold the skin taut. Then trace a very fine black line along the inner lid, below your lashes. This will make your eyes pop and your lashes look fuller without it seeming like you're wearing any make-up.
For a dramatic look, smudge black eyeliner on with your fingers or a cotton swab.
If your eyes are on the small side, avoid lining both top and bottom lids in black--this can make the eyes look smaller. Line just the bottom lash lines. If you do line the top lashes, use a lighter color, like gray, on top with black on the bottom.
If your hand tends to get unsteady while you apply liner, rest your elbow on a table.
Try applying black eyeshadow over the top of black liner. Dip a small, angled shadow brush into matte black shadow and carefully trace over top of the liner. This will help the line last throughout the day and make it look more intense.
If you're using a pencil, make sure it's sharp before you apply the liner. If you're using a cream liner, wipe the applicator brush clean before dipping it back into the pot to prevent any dry clumps of liner or stiff bristles from messing up your look.