Before starting this project, you'll need to break up flea-market plates or tiles for the mosaics of these colorful stepping-stones. To do this safely: Place tiles or plates in a shallow box and cover with a cloth to prevent shards from scattering. Wearing safety glasses and using a hammer or tile pincers, crack the ceramic into large pieces. Handle them carefully, they'll be very sharp. For variety, use pebbles, shells, jewels, colored glass, or marbles for this project in place of the ceramic pieces.
See below for a materials list and complete instructions.
1. Immerse a concrete stone in water to wet it thoroughly. Prepare thin-set mortar in bucket according to package directions (consistency should be similar to slightly runny peanut butter). Using notched trowel, spread a 1/4- to 1/2-inch layer of mortar onto part of stone.
2. Arrange pieces as desired, pressing them lightly into the mortar and continuing across the stone. Add extra mortar under the pieces, as needed, to achieve a fairly even surface. Leave crevices between all pieces for grout. Clean excess mortar from the surface and let the stone dry overnight.
3. Mix grout according to package directions. Scoop a large amount onto the stone, using a spatula or trowel to spread it out and push it into gaps. Add as needed, removing excess as you go. Smooth grout on the sides of the stone as well. (Note: You may use mortar in place of grout.)
4. Using a wet sponge, clean excess grout from the sides of the stone. Wipe down the top, going over the surface in both directions and rinsing the sponge often. Repeat, taking care not to remove too much grout from the gaps. Let the stone dry 24 to 48 hours, then buff it with a soft cloth.