The sole edges can start to look a bit sad after some wear, but this can be fixed!
Brush the sole edges free from sand and dust.
Use the sandpaper to level out the sole edges. Be careful not to scratch the upper leather.
Use the paintbrush to paint the edges with leather dye. Several coats of paint is probably needed. Be careful not to stain the upper leather.
Let the sole edges dry for an hour or so before moving on.
Apply shoe polish to the edges. This can be done by stroking a dryer piece of shoe polish against the edge. Use the cloth to buff up some shine, similar to the shining.
The sole edges has gotten a more even colour and some shine. Much better than before!