Visit a nearby market and buy a blue and red leotard. You can buy the leotard with or without glitter, depending on your own choice. Also buy some amount of stick on jewels and use them to write “Katy” on the side of the leotard you just bought.
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You will also need a blue coloured belt that fits you. If you find a good belt which you like and it does not fit you well, then you can ask the shopkeeper to adjust to your size. Usually, the belts can easily be adjusted by making extra hole in the belt or cutting off the extra piece from the buckle side.
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Visit a nearby craft store and buy around 20 big peacock feathers. You can now use hot glue to stick the feathers with your belt and wait for about 10 minutes to allow the glue to get dry.
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You should also buy a blue wig, which you will wear after you wear the Katy Perry peacock costume. Blue hair colour is something that most women will try to avoid to be used in regular routine. Therefore, using the blue coloured wig will be the best option. Moreover, you should also buy peacock feather earrings.
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Buy a peacock statue and a blue coloured headband. Use the glue to stick the statue on the headband and wait until the statue firmly sticks on it. Wear everything and you will look like Katty Perry.
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