One crusty way is to make friends with someone who is the same shoe size as you but opposite stance. Both of you skate your shoes (same shoe model ideally) for awhile and then trade with each other: either the whole pair or just one of them depending on how you both want your shoes to wear.
Sanding down razor tail on an actual sander or some make shift contraption.
Visible crack? Fill it in with super/krazy glue and clamp it while it dries.
Got a chip? Find some woodchips or sticks, smash em and glue them together in the desired shape, and use some left over grip scraps if you can get your hands on em. Then grip over the filler you put in the chip, cut excess and back to skating!
Pro tip! Just don't skate and your gear will last eons