A couple of other hints that I’ve found to be effective:
1) Wear a smoother material pant. Personally, I prefer khaki tactical pants which helps seeing any ticks trying to catch a free ride a bit easier. Also the smoother fabric doesn’t help them cling as much, unlike denim. Think of regular hiking pants as well.
2) If the pant has some sort of Dupont water-repellent finish, take some extra care when applying Permethrin to them. Lay them flat on a picnic table and spray liberally, then use a Permethrin soak rag to wipe the side down. Let dry, flip and repeat. I’ll usually do two coats to ensure full coverage. Also do the first two-inches inside the pant leg bottoms and inside the waist. Permethrin is designed to kill the tick, not just as a repellent.
3) Also, don’t forget other articles of clothing: socks, shoes, bandana, etc.
4) There is also the option of buying clothes already impregnated with Permethrin. After a hike in here in Eastern TN earlier this year, I actually found two dead ticks on my socks (ExOfficio brand) which came already impregnated with Permethrin.
A useful, inexpensive that works really well too is the Tick Key: https://tickkey.com/
In reference to your 4)
I had a guy working at my house doing some excavation in September. He had clothes he said he sent back once year to the manufacturer to get retreated with permethrin. I do not know the brand, but they were all a lite smooth khaki color. His shirt looked like one of those fishing shirts.