Moleskin padding is a cushioning tape that you can cut into strips and stick on the inside of shoes, right on the spots where they rub your feet. Simply cut the Moleskin tape to the right size, remove the adhesive strip, and stick into position.
I find Moleskin particularly useful to stick on the inside of footwear tongues that rub the vamp of my foot. I recently did just that with two pairs of oxfords that would rub my skin raw in those two tiny spots on the tops of my feet. It eliminated the rubbing very effectively.
In the past I have placed Moleskin on the inside of the shafts of boots so that they don’t rub my shins as I stride. It has also saved my pinky toe from being rubbed red. Moleskin is a good shoe doctoring tool to have on hand.