shape up

verb

To improve; to correct one's bad habits or behavior.
“He'd better shape up soon, or he'll fail the class.”
“You better shape up 'Cause I need a man And my heart is set on you”
To take shape; to transform into or become.
“The fog has vanished and it's shaping up to be a beautiful day.”
“Pretty good. A full refrigerator! I can see this afternoon is shaping up just great.”
To gesture or posture threateningly; to approach as if to fight; to pose to intimidate.