do something until you are blue in the face
until (one) is blue in the face
For a great or unending length of time; until one has done it to exhaustion. You can complain about it until you're blue in the face, but you're going to school today whether you like it or not. They are such strange friends. They'll argue until they're blue in the face, then they'll go out for dinner and be the best of pals.