1. That's not how I act.

2. That's not what I like.

A justification for how someone behaves

What someone would say to insinuate that it was their style, or that it was the way they usually do things.

That is how I like to do things.

used to affirm one's impressive attribute

A completely arbitrary and pathetic way to excuse any sort of behavior. By defining an action or ideal as "how you roll", you make whatever you're describing perfectly acceptable to any and all audiences. After all, it's how you roll.

The phrase used in response to a question you do not know how to answer