You don't need to use any kind of chemical / expensive treatment.
Easiest way, cover your hair in conditioner and comb through with a nit comb (got two off ebay for about £1)
Get out as many of the eggs and lice as possible.
Repeat this every two days until all of the eggs have gone.
Lice follow a lifecycle of breeding, laying eggs, hatching then breeding.
If you can break the cycle and get rid off all the live lice you then will only have the nits (eggs) to contend with.
Chemicals will not kill the eggs, so they can still hatch if you don't get them out.
If a fine tooth nit comb is not catching them, use your finger nails to pull along the hair and out.
I know they are a nightmare, but if you regularly check with the conditioner method you will keep them away.
Vinegar does work to kill the live lice, but won't kill the eggs.