I wear out the soles of walking shoes, leaving uppers still in great shape. Recently I used one old pair to patch the soles on the other pair, breathing some new life into shoes that would otherwise go to landfill.
Step 1: Materials
-2 pair worn out shoes, one of which still has some life in the uppers.
-a carpet knife
-shoe adhesive, such as Shoe Goo
Step 2: Evaluate the Shoes
Each of us wears out the soles of shoes in our own particular way, based on our gait. For instance, I wear out the back outside edge of the heel before anything else. Look at the worn out areas on your soles, think about how much needs to be patched, then look at the donor shoes and identify less worn areas that would create the needed shape for the target pair. (I recognized that I could use the back inside edge from the opposite foot on the donor shoes to take the place of the worn out area on the target shoes.)
Step 3: Cut Out the Patches
Measure the sizes of the patches needed by the shoes you're fixing, then use the carpet knife to cut them from the shoes you're sacrificing. Cut away as much underlying foam as required from each patch to fit the surface of the target shoe.
Step 4: Prepare the Target Shoes
Cut any remaining sole off the area you'll be replacing on the target shoes, then even the surface by cutting away foam as necessary.
Step 5: Dry Fit the Patches
Place each patch in its location on the target shoe without applying glue. Make sure it fits; if it doesn't, trim the patch and/or target shoe until it does.
Step 6: Glue It Up!
Follow the directions for your shoe glue to glue the patches in place. Be sure to wait until the patches are dry before trying out the shoes.