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There are two ways you can go about this. You can base your costume off of an existing Katy Perry outfit, or you can create your own Katy Perry-inspired costume. If you are going to recreate a specific outfit, follow the tips in this section, or take a look at one of the other methods.  Have lots of reference pictures printed out or saved online. Try a theme. A lot of Katy Perry's looks include cats or candy. Katy Perry is known for her bright, colorful, and unique patterns. Most of her looks feature a 19050s, style dress with a full-circle skirt, but she also has worn A-line dresses and tube dresses as well.  You can always modify the dress by gluing wrapped candy to it, such as: Lollipops, Tootsie Rolls, and Smarties.  Use stencils and fabric paint to add a large cookie, cotton candy, or peppermint candy print. The higher the heels are, the better, preferably at least 4 inches (10.16 centimeters). If you aren't comfortable wearing heels that tall, you can try regular heels or even Mary Janes, but keep them bright and colorful. Here are some colors and styles to look for:  Clear shoes, preferably green.  Pink, glittery Mary Janes.  Bright, solid colors. Katy Perry had her hair in almost every color imaginable. Her most memorable hair colors were blue, purple, and pink. Most of her hair styles were simple, shoulder-length cuts with straight bands that end just above her eyebrows. She also wore lots of vintage styles inspired by the 1940s and 1950s. Here are some suggestions:  Wavy, dark purple, shoulder-length wig with a side part and no bangs.  Shoulder-length lilac wig with the bangs rolled in a 1940s or 1950s fashion.  Wavy-curly blue wig that falls past your shoulders with straight, full bangs.  Green wig, shoulder length, with blunt bangs. Katy Perry's looks are bright and colorful, and no two outfits are alike. She seems to have a certain go-to look for her makeup, however, that focuses on shimmer, bold eyeliner, and thick, heavy falsies. Here's how to get the basic look:  Cover your lid with neutral eyeshadow (preferably beige). Add grey, silver, or gold into the crease. Cover the lid with sheer, shimmery gold shadow or shimmering dust. Apply thick, bold eyeliner to your upper lid. If you can, do a cat-eye or wingtip. Apply winged faux lashes—the thicker and heavier, the better! Keep the rest of your makeup subtle with pink blush and pink or red lipstick. Your accessories should reflect the theme, color, and patterns of your outfit. Does your outfit have a lot of candy on it? Pick a chunky bangle with candy cane stripes on it! Can't decide? Grab a microphone or a pair of cat-eye sunglasses! Listed below are some ideas to get you started:  Cat-eye sunglasses Microphone (handheld or head) Thick, colorful bangle bracelets A headband with hearts on it. Nab it during Valentine's day!  Pink tights or thigh-high stockings.

Summary:
Decide on what look you want. Choose a colorful dress with lots of interesting patterns. Stick with bright, colorful heels. Find a bright and colorful wig. Go bold and heavy with the eye makeup. Complete your outfit with matching accessories.