OUTDOOR TIPS:

Seek shelter: if you can hear the thunder within 30 seconds of seeing the lightning then the storm is close enough to put you at risk.
Stay low: Avoid being the tallest thing around. Squat or lie down under shrubs or smaller trees with your heels together.
Avoid tall trees: Don’t stand next to the tallest thing around either. You can be hit by a side flash if you are under a tall tree.
Stay out of the water.

INDOOR TIPS:

The best shelter: The best shelter is a building with plumbing, electric wiring or other metal in it. Other structures offer little protection.
A car offers protection: Roll up the windows and don’t touch anything metal though.
Don’t touch: Once indoors, wear insulating shoes and avoid windows. Also don’t use or touch any plumbing, metal, or electrical appliances, especially a non-cordless phone.