Outdoors, use a tick drag or carbon dioxide trap to locate the ticks and reduce their numbers.
Remove woodpiles and other areas where mice may live and keep bird feeders away from the house. Keep vegetation cut below ankle level to reduce tick harborage.
Do a tick drag: A tick drag is a 4' by 6' piece of white flannel attached to a stick. You drag the flannel through the yard. Any ticks in the vegetation will attach themselves to the flannel where they can be seen and destroyed.
C02 Trap: A carbon dioxide trap is simply a covered ice bucket or styrofoam container with several holes in the sides near the bottom. Place approximately 2 lbs. of dry ice in the bucket and place the bucket on a piece of white flannel or a piece of plywood with a masking tape barrier. The tape should be stapled to the plywood around the edges with the sticky side up. If you use flannel, inspect both sides for one to three hours after trapping begins. The dry ice should last about three hours and attract every tick with a 75 sq. ft. area around the trap.