Outdoor Mod Podge
Clear Glaze (Sealant)
I bought a couple of extra tiles from Lowes for 16 cents. These are super cute, easy gifts. I'm glad I bought a bunch, I was addicted after making one set.
Start out by cutting the felt into squares. It will be glued to the bottom of your coasters to protect the table from scratches AFTER everything has been sprayed with sealant. Coordinate a couple rolls of washi tape, finally decide on a cute pattern and start taping the tile. I left about a half inch of tape on the bottom of the tile so the sides are covered and once the felt is glued down it will keep the washi from coming up as well.
After the entire tile is taped, go over it with Outdoor Mod Podge and let it dry. I sprayed my tiles with a couple coats of Clear Glaze as well for extra protection against water, etc. Better safe than sorry (I think I just aged 30 years with that expression). When it's dry, hot glue the felt to the bottom of the tile and TA DA it's a coaster.