You will need:
A mailbox or any type of box with a lid from a craft store
Paintbrushes and paint
A hand written love letter
In craft and fabric stores you can pick up a wooden mailbox that is prepped for you to paint. If you can’t find a mailbox, you can use a regular box or even a large treasure box if desired.
Use two coats of whatever base paint you would like. For wooden surfaces, acrylic paint works great and it’s pretty cheap. Make the paint relevant colors, such as your partner’s favorite colors, the colors they were wearing when you first met, the color of their eyes, etc.
The easiest way to paint a wooden surface is to use a stencil. After the base paint has dried, tape the edges of the stencil against the surface and gently paint over the stencil. Use something symbolic or simply romantic.
After you’ve finished painting, use the box on a regular basis to leave notes and trinkets for your sweetheart.