Here are a few ideas to get you going.
All you need is a plain white sheet (flat, not fitted!)
and a scissors to cut out eye holes.

In just a few minutes, you’ll be good to go.
To really get the idea across, carry a rock or a whole bag of them.
(Alternately, you could go with a leopard-print theme, shown here.)

Pick up a cat-ear headband, likethis onefrom Forever 21.
Press-on nails from the drugstore make instant claws.
For your face,YouTuber Sonia Castanedahas some pointers.

Use liquid eyeliner to create a dramatic cat’s-eye effect, followed by bold smoky eyeshadow.
Lightly shadow the hollows of your cheeks with a dark beige blush.
Use a light pink or peach lipstick on your lower lip.

If you have a plaid shirt and overalls, you’re already ahead of the game.
(This hatfrom Party City is a budget-friendly $3.)
It’s all in the makeup.

Add freckles on your cheeks if you like, and draw exaggerated lashes on your lower eyelid.
This tutorial collection fromGlory of the Snowoffers a variety of options.
(Cue the groan.)

(Cue the groan again.)
The possibilities are as endless as your ability to personify common phrases.
How could you dress as “assault and battery”?
A “smart ass,” “rotten egg,” or “superstar”?
What if you wore a large circle with the word “tuit” written on it?
(Think about that one for a second.)
Wigs, hats, and an accessory or two can be all you need.
Simplest of all: a witch’s hat.
There’s nothing that says you have to “be” anything specific for Halloween, either.
The important thing is to have fun going outside your usual fashion comfort zone.