be on best behavior

manage

control direct

act correctly act one's age act with decorum be civil be good be nice be orderly comport oneself conduct oneself properly demean oneself deport oneself discipline oneself keep one's nose clean keep the peace live up to manage oneself mind one's manners mind one's p's and q's observe golden rule observe the law play fair shape up toe the mark watch one's step

act up misbehave