Some ways you can prevent corns from forming on your feet are.
Dry your feet thoroughly after washing them and apply a special moisturizing foot cream to your feet.
Use a pumice stone or foot file regularly to gently remove the hard skin causing the corns on your feet.
And last wear comfortable footwear that fits properly as shoes that don't fit properly can aggravate and bring on the corns on your feet.
Properly fitting shoes let your feet breathe properly and don't constrict the toes so properly fitting shoes are a must.