stepping your game up
When in a relationship. hooking up with a girl that is hotter then your girlfriend.
Hey didn't you cheat on Amanda....... Nah i stepped my game up by hooking up with Amy. yea your right you were just stepping your game up.
step your game up
improve your skills or talents.
You gotta step your game up to make in in the rap biz.
Step Your Rap Game Up
Commonly used to tell rappers that their rhymes are whack, but can also be used when telling someone to improve something.
"John im afraid you got a D....Step your rap game up son!"