Here's how I made these...
1. Paint the blocks
2. Cut paper to fit the blocks
3. Use a sponge paint brush to apply Mod Podge to the block (apply this lightly or you will get bubbles underneath the paper)
3. Apply a light coat of Mod Podge over the paper
4. I sanded all edges of the blocks just before the paper was completely dry but this depends on the look you want. You could also use distressing ink for a vintage look.
5. Apply vinyl letters (I used my Cricut Expression for cutting). If you don't have a cutting system, stickers would work great.