Just as face powder helps to set your foundation, a powder (in the form of eyeshadow) placed over your liner can help it set and last longer. Simply draw on your liner, then take a small eyeliner or smudger brush (I like the Lancome #10 or MAC 212) and apply your choice of powder eyeshadow over where you placed the pencil. It's that simple!
For added staying powder without changing the look of your pencil line, choose a shadow shade close to your pencil, and use a thinner brush to place the powder on top of the pencil line. For a bit of added interest, try changing up the shade of your liner by layering it with different shades of shadow.
This trick is also perfect for people who aren't super-comfortable applying liner, or those that just prefer a less harsh line. Work the shadow into the liner with short, back and forth motions, which will blur the line a bit. This gives a softer, lightly smoky effect that hides the effects of a shaky, unsure hand!