Materials:

• A t-shirt in your size (any color will work, but a white one makes the polka dots really pop!)
• 3 bottles fabric paint, each a different color (pick any color combo you like, but some ideas: 3 shades of the same color; red, blue and yellow; and yellow, green and blue)
• Circle stencils, with at least three different sizes of circles (available at any craft store; you can also make your own circle stencils by tracing some drinking glasses onto stiff cardboard and cutting the circle out)
• A paintbrush
• A large piece of thick cardboard or a magazine you no longer want

DIY Step-By-Step:

1. Make sure your t-shirt is washed and ironed.
2. Lay the t-shirt on a flat surface, the front side facing up. Between the front and back layer of the shirt, place a piece of heavy cardboard or a magazine.
3. Position your stencil somewhere on the shirt. Hold it in place (you could temporarily tape it into place for extra support), and begin painting inside the stencil with the fabric paint.
4. Once you're done with the first circle, carefully pick up the stencil (you don't want to smudge your perfect circle) and move it to another place on the shirt. Paint another circle in a different color. Continue this process, using different colors and different circle sizes, until you have as many circles as you like on the shirt.
5. Let the shirt dry for several hours, and it will be ready to wear!