" Monkeys are caught in a number of ways, but one of the most unique ways is a do-it-yourself project. Make or perhaps get a large sturdy wooden box out of dunnage or plywood and modify it so that one side is mostly wire-mesh. Drill a hole into one of the adjoining sides that is just large enough for the monkey’s hand to fit through. Finally, place a banana into the box through a trap door installed in the bottom of the box.
The result should be that the banana in the box is visible to the monkey through the side having the wire-mesh. Seeing the banana, the monkey will reach through the hole, grab the banana and then try to pull it through the hole. Of course, having made a fist around the banana makes the monkey’s hand too large for it to be extracted. Normally the monkey’s greed will overcome his intelligence and he won’t let go and Voila, you have caught the little critter and now the fun begins!
The difficult part is separating the monkey from the banana and the box without the monkey biting and tearing your hand to shreds. This part works best if you have a large cage which you can use to transfer the monkey into. However, wearing gloves is definitely a given! "

― Hank Bracker