This is the classic war poster "Keep Calm and Carry On" reworded to "Keep Calm and Party On". I've kept the traditional crown at the top, but added silhouettes of dancing/partying girls on and around the letters. It makes a cool eye-catching stylish design that's different to the other keep calm shirts/posters out there.
I've put this on a purple background, but you can change that really easily. Hit 'Customize it' and then 'edit', and you'll be able to change to absolutely ANY color you prefer.