Whatever you use, you MUST comb with those special combs at multiple times a day until you see no more lice/nits. That is one of the best ways to avoid re-infestation. I did the chemical stuff but didn't do the combing, and those critters came back! And i got it too! ugh. No one wants to comb mama's hair :glare: And what a pain it was to comb my own.
The usual place is behind the ears and back of the head (they like warmth), but you should definitely run a comb throughout the hair. If you have boys, give them a buzz cut.. it's is TOTALLY worth it.
I would also buy some Neem shampoo. It is a lice repellent... it won't kill them, but they don't like the stuff. It's not very nice smelling, but it is natural. It got mine off Amazon.
Good luck.