I love cateyes, they are incredibly simple, fun and sexy! All you need is some liquid eyeliner, typically black. If you find it tricky to use liquid eyeliner or are inexperience with makeup pointed Q-tips dipped in makeup remover or makeup remover pens are great for smudge removal. Some of my favorite liners are the Maybelline Master Precise Ink Pen and the Covergirl Liquiline Blast.
1. start at the inner corner of the eye where the line should be the thinnest
2. angle your brush and do short feathering strokes
3. to get the perfect wing follow the line of your bottom lashes or use a credit card and hold it at a 45 degree angle from your nose
One of my favorite celebrites is Emma Stone and she always perfectly executes the cat eye and looks effortlessly stunning.