give (someone) the high sign

To use a hand gesture to signal someone about something. Sometimes, it refers specifically to the "OK" gesture (when the tip of the index finger and thumb touch, forming a circle). I'll give you the high sign when it's time to come out on stage. A: "Are you sure we should have taken the cookies out of the oven?" B: "Yeah, Mom gave me the high sign." Don't call that guy back until the boss gives you the high sign, OK?