From The Costco Connection:

For years the best recommendation for preventing getting ticks on you is to treat those recommended long clothes with Permethrin products which are much more toxic to ticks than DEET.

on Amazon: Sawyer Premium Permethrin Clothing Insect Repellent Trigger Spray, 24-Ounce
How to Use it — read the comments too.
Permethrin side effects (when used as a topical ointment)
the must-read warnings

My boys spend a lot of time outdoors so I worry about them getting Lyme disease. But I’m not sure this is the best solution either. Surely there’s a more natural product so I don’t have to worry about toxicity?

Ways to avoid ticks, from the CDC.