Mow lawns. Chiggers like long grassy and bushy shady areas. Mowing lawns and removing unnecessary shrubs or weeds is best way to decrease their population. Spray your skin and clothing with deet or Permethrin repellant. Avoid walking in areas likely to harbor chiggers. Wear long pants and long sleeved shirts, thick socks and high boots or shoes with pants tucked into the boots.
Insect repellents. You may wish to use fda approved insect repellents as well as sensible clothing choices that have long sleeves, tuck your pant legs into boots as well to offer more protection for the legs. Also try to avoid heavily wooded areas if possible.