Vinegar.

SOAK hair in vinegar, wrap in glad wrap and tie a plastic bag or similar around head so no air gets in or out. Leave for a number of hours.

This creates like a little fumigation tent...the lice die from the fumes.

Rinse out vinegar and dead lice and repeat in a few days when the new eggs hatch (becuase the fumes wont kill eggs...but will get the freshly hatched lice before they breed).

Don't shampoo the hair afterwards.

The vinegar won't make hair smell.

For the added benefit of making your hair super pretty, soft and shiny too - use Apple Cider Vinegar!