make a monkey out of someone

make a monkey out of someone

or

make a monkey of someone

OLD-FASHIONED
If someone makes a monkey out of you, or makes a monkey of you, they do something that makes you seem ridiculous or stupid. The teenage footballer made monkeys out of men twice his age with his spectacular goals. If you follow the proper steps, you won't make a monkey of yourself.
See also: make, monkey, of, out