Select a surface for growing the lichen. The surface can be a rock, tree or garden statue. Whatever surface you chose, it must be in a shady spot.
Fill a spray bottle with milk. Collect 2 tsps. of lichens from the same environment where you want the lichens to grow. Crush the lichen flakes and pour them into the spray bottle with the milk. Gently shake the bottle to mix the solution.
Spray the surface where you want the lichens to grow liberally with the milk solution. Soak the surface until the milk runs down the material. Do not spray the surface on a wet day or the rain may wash away the lichen spores.
Repeat the application once a week until the lichens begin to grow.