I took an old stick-on nametag, and cut two squares out of it to make my stencils. I used a heart-shaped craft punch to make my design, but you can choose whatever shape you want.
Peel off the back of your stencil, and arrange the design how you want it to appear on your nail as you stick the stencil on your finger.
Smoothly apply a layer of nail polish in your desired color to the top of the stencil, making sure your shape is neatly covered. I used gold crackle polish on top of clear here, but in hindsight I realized it would have been better to go for a stronger contrast!
Let the polish dry, then carefully peel stencil away. Apply a coat of clear polish to the entire nail to seal the design in place and make it last longer. Repeat on other nails as desired; you can probably reuse one stencil at least 4-5 times before you need to make a new one. Enjoy your fun nails!