Keep rucking!
Since every one has a pair of feet, you should get some good answers, but varied.
Keeping feet dry is critical. Rub your feet with powder and add a dash to your socks.
Change your socks.
Loosen the boots around your ankles to let blood circulate.
Flex your feet and toes.
If this fails , recite the following phrase to yourself,
" Discomfort is a state of mind."