Thanks to celebrities like Taylor Swift the "Cat Eye" has made a huge comeback in the make up world. Many people tend to think that in order to achieve this look you have to use liquid eye liner. For me, when doing this look on myself or someone else I like to use gel liner. It's a nice in between consistency when applying. As long as you have the right brush for application you are golden. So here are a few quick tips:

Before putting on your eye make up add some concealer and it will stay in place all day.
To not look too "done" only take your liner half way across the top. (I do this for every day no matter which kind of liner I'm using)
Always use a slanted brush when applying gel liner. Doing this will make it much easier to draw your perfect line.
Sometimes you may want a more dramatic look, sometimes not so much so always start out less extreme. Also don't think about it too much just follow the natural line of your eye lid and go from there.

But one major tip, don't drive yourself crazy trying to make the perfect Cat Eye. It will be okay I promise. Taylor wouldn't approve of tears shed over eyeliner. Practice makes perfect!