How To Get Rid Of Dark Patches And Blisters On Feet?

Dear Dr. I have always been concerned for my feet and wear mostly covered ballerinas to hide the disgrace. However I have several shoe bite marks on the toes especially the last toe, the marks are very hark and the last doe has developed somewhat hard and dark blister. Please suggest what can i do to reduce teh dark patches as well as smoothen the blisters