EXAMPLES FROM THE WEB FOR SMARTEN UP
At the tavern, where we went to smarten up and to eat, we chanced upon Gregory.
I had done my best to smarten up my uniform, and make all my accoutrements bright and glistening.
That did not take her half-an-hour, but when she came down the woman had done her best to smarten up her room.
The next day we had to smarten up and get ready for the Brigadier-General, who was going to inspect us.
The guide suggested that we smarten up our gait, and we put the horses to a canter.
Next day he sent for the senior officer, and after a short talk with him told him to smarten up his subaltern.
Take my word for it, George, Ox Lease will have to smarten up a bit for this young lady.
But I've got a hunch that if we play dumb at first, then smarten up slowly, we can make him feel that he's done it for us.