Mascara is great for making thin lashes stand out, or adding an additional pop to already thick lashes. It's far cheaper and easier to use than fake lashes, which makes it a great thing to add to your quick morning routine.
If you curl your eyelashes (and you should!), it's best to curl them before applying mascara. Trying to curl your lashes after applying mascara usually results in mascara all over your eyelash curler, and not on your lashes where it belongs.
Start by pulling the mascara brush out of the tube, and placing it at the base of the lashes. Wiggle it back and forth to place mascara at the roots of your eyelashes. Darkening the base of the eyelashes is how mascara makes lashes seem thicker. This is also why techniques such as tightlining work so well.
After you've deposited a bit of mascara at the base of the lashes, pull the mascara towards their ends, to reduce clumping. Then, close your eye and brush mascara over the tops of the lashes, further reducing clumping. You should have a nice, even application of mascara at this point. Once you have applied the mascara, wait a few seconds before opening your eyelashes, or else you'll sling mascara on your eyes.
Mascara is one of those things that doesn't keep permanently. If you notice a change in odor of your mascara, or it starts applying differently, throw it out and buy a new one. Most mascaras keep for anywhere between 6 weeks to 3 months, so plan on replacing them before they go bad.