Don't wear tennis shoes - these are a magnet for ticks. Rather, put on some high rubber boots as suggested. When the ticks are really bad, I have doused myself with DEET spray in a bad tick year and still got a dozen on me. I have not tried the permithrin, but I plan to!
The best advice: When you get back in, do a complete change of clothes and do a careful check. And place the clothes in the laundry or outside as they probably have a bunch of ticks clinging inside them, so you don't want a bunch of ticks in your house. Then check again before you go to bed. If you get the tick off you before it has much time to imbed, your chances of getting Lyme's is far less.
MZ... Deet makes ticks fat, it doesn't work. they don't make tick/flea powder with permethrin cause deet works better.
RR