1 to repair or decorate a building so that it looks attractive:
She always does her presents up beautifully in gold and silver paper.
If you put any more in that suitcase you won't be able to do it up!
He's put on so much weight that his best trousers won't do up any more.
If you don't do up the cage properly the hamster will escape.
They reckoned it would take six months to do up the house before they could move in.