Choose a shoe and the type of plant you'll be using for your shoe-planter project. Pick smaller plants -- succulents are ideal for their hardiness and compactness -- as your space will be limited.
Drill 2 to 4 tiny holes in the sole of the shoe to let the water drain out. Don't make the holes too big, as you don't want the dirt to spill out.
Fill the bottom of the shoe planter with a thin layer of rocks. This will help the water drain out and prevent water from collecting and drowning your plant. Pack potting soil on top of the rocks. If you're using seeds, pack the soil to about 1/4 of an inch from the top of the shoe. If you're using a pre-grown plant, pack the soil halfway, position the plant and pack the soil on top of the plant to secure it in place.