Get on the outside of that!

By using the idea that if something is inside you, you are then outside of it. Commonly used for drinking buddies when the drink is placed in front of you for enthusiastic consumption.
Alternatively chicks could use it to describe a guy they fancy getting a length from

*Returning from the bar*
"Get on the outside of that Fella!"

*watching hot bloke walking by*
"hey girlfriend, wouldn't you just like to get on the outside of that!"

you getting outside of yourself

When a person acting to big, like something they aren’t

Bro, you need to cool out… You getting outside of yourself