Recognize that electricity is in the air.  Even if clouds have yet to produce lightning, electricity may still be in the air.  The best method of detecting danger is to closely observe your or your hiking partner's hair.  If you see that hair is beginning to raise into the air you know that it is time that you high-tail it out of the area you're in and seek shelter.

Always follow the "30/30 Rule."  Upon first sight of lightning, count the seconds that pass until you hear thunder.  If the number of seconds is 30 or less, seek shelter immediately.  Stay put for 30 minutes after the last lightning flash or rumble of thunder.  The National Weather Service estimates that 50% of all lightning deaths are sustained after  the storm has gone by.

Avoid dangerous locations.  Stay near shelter during a storm; avoid terrain above timberline and bodies of water.  If lightning moves in, try to avoid being within 100 yards from the nearest body of water.  Thunderstorms in Colorado have a propensity to build up steam between 12:00 p.m. and 3:00 p.m.  Realistically, if thunderstorms are in the forecast you should never be above timberline after 1:00 p.m.  If you are above tree line when a storm rolls in, rapidly descend to shelter.  Avoid caves - they actually channel electricity fairly well and are extremely dangerous to be in during a storm. 

Avoid isolated trees and high points.  It is always better to seek shelter in a thick forest versus an isolated stand of trees.  Lightning favors small groupings of trees over dense stands.

Choose your camp wisely.  Do not pitch your tent next to the tallest trees in the area.  Lightning-filled storms can develop during the middle of the evening.  Once again, it is best to locate camp in a thick stand of trees instead of next to an isolated grouping.

Discard metal objects.  Drop all metal objects during a storm.  Such objects might include an internal or external frame backpack, trekking poles, etc.  Furthermore, you should get off of a bicycle if you are mountain biking or road biking and a storm is closing in.

Avoid open fields.  However, if you are stuck in an open field and cannot find shelter, find the lowest possible area.  Crouch with your head low and keep your feet together.  Never sit or lie down on the ground.  Both of these positions facilitate greater ground-body contact, which gives lightning a wider space to travel through.

Spread out.  If lightning is imminent and you are in a group, try to spread out. This will minimize the chance that everyone in the group will be struck.  It is important to ensure that at least one person will be able to respond to an emergency situation.

Remain calm if someone is struck.  If somebody is hit by lightning, respond by providing the proper first aid.  If the victim is not breathing, provide mouth-to-mouth resuscitation.  However, if the person no longer has a pulse, the responder should attempt to provide cardiopulmonary resuscitation (CPR).  Someone from the group should stay with the victim until help arrives.