Police officers all wear a uniform to do their job, and it's an outfit that makes them easily recognisable to the public and earns them respect. It's easy to make a policewoman fancy-dress costume, and you can adapt the look to suit your own tastes -- making it as smart or as sexy as you please.
Draw two police badge-style shields on the card. Make them both about 2 inches in height. Cut them out with the scissors.
Glue one badge to the front of your cap and leave it to dry. Glue one to the left front pocket of your shirt and leave it to dry.
Dress in your trousers, shirt, belt and boots. Put your hat on and attach the handcuffs to your belt. Place the toy gun in your pocket and wear your aviator sunglasses.
If you want to dress a bit sexier, swap the trousers for a short skirt and the shoes for knee-high boots. Pick a tight shirt, too. You could go for a navy blue uniform instead of black. If you don't have a front pocket on your shirt, glue the badge where one would usually be.
Don't make the outfit too realistic or use it to pretend you're the real police, or you could get in trouble for impersonating an officer.