One thing that many diabetics get and often dont think about are blisters and calluses. Some people still sand or smooth calluses down or cut them off, and others use pumice stones.
Any callus is indicative of ill fitting shoes or foot problems and the foot is trying to protect itself.
I got rid of mine that easy way.. lotion and socks.
After takinga nice soothing bubble bath I used Sarah mitchell foot lotion inmint and then put on some comfy chusy socks. It a few eeks the calluses wre gone.

Now blisters are another problem. Blisters are also caused by seams in shoes, rubbing shoes or irritation. In many diabetics they turn to blodo blisters where the capillary is injured as well. these trn into clots that eventually fall off as new skin pushes it up, and a callus forms.

You can drain a blister if you follow good rules. Clean withBactine or alcohol swab. Using a lancet poke a single tiny hole so that the blister can drain. apply Antibiotic cream and cover with a badage so it doesnt get dirty.
the pocket will turn slightly hard and can then betrimmed ff before it becoms a callus.