Beware the speed bumps!
Overuse of a word, sentence, or phrase is like hitting a speed bump at 90 mph. It hurts. The objective of a good writer is to draw the reader into the story, much like being in a dark theater, but without the nifty lighting. If they are able to pick out and count the word on more than one hand in a single page, you're doing something wrong. (Note: this does not include such words as 'and' and such for the most part, but even they can be overdone)
Ex: Tiffany was like, the most irresponsible girl in the world. Like, she always forgot to do her chores, and like, never did her homework. Her mom was like, so fed up.
The overuse of the word 'like' is akin to nails on a chalkboard for some people, so remember that too much of something is not a good thing.