A short-term bout of stress is harmless.  The real problem is chronic stress, which is sustained over months or years.  If chronic stress is consuming your life, or if you just want to make sure it stays away, then here's some great tips for you:

Relax: It's really not as difficult as it sounds.  Everyone has their own different ways to tune out and gear down; you probably know yours.  It doesn't matter what you use as long as you take the time to practice your personal stress relievers.

Exercise: Get moving!  Exercise to force your heart to beat faster is probably the top way to combat stress.  It gives your body the chance to respond in a physical way, without endangering yourself or others.

Improve your environment: The modern clutter of sounds, sights, and smells can keep you on edge.  Avoid living in places that are submerged in a din of traffic noise or punctuated by the late-night shout outs of nearby noisy neighbors.  Don't just reduce the noises, but clear out all that unnecessary amounts of information, which includes everything from busy posters to disorderly desks.  Television and the Internet are constantly grabbing your attention and causing stress.

Mentally reframe the situation: Stress is the result of what goes on in your brain, not what happens in your environment.  if you picture an obstacle as a worthy challenge rather than an infuriating disaster, you'll feel better.  Similarly, don't worry about the things you can NOT change.  Don't expect yourself to perform perfectly at all times.  remind yourself of the UNimportance of trivial upsets.  And don't assign the same priority (super-ultra-high) to everything on your to-do list.

Sleep: A lack of sleep leaves your brain unable to regulate its emotions.  If you're in this situation, you'll find yourself emotionally out of control and unable to rein in big reactions to little annoyances.

Seek social interaction: Studies show that communal activities distract us and relieve stress.  Sharing a laugh and nurturing a family member are particularly effective.

Assert yourself: A key component of stress is a perceived lack of control.  Without any way to respond, the brain's built-up energy is channeled into smoldering frustration.  To avoid becoming a victim, speak your mind, make decisions, and be honest.

Perform good deeds:  Altruistic acts help stamp out stress.  The effect probably works because it boosts your sense of control, lightens your perception of the world, and enhances your self-image.

Know your stressors and when to avoid them: Sometimes a good debate is a lot of fun.  Other times, it might send you quickly over the edge.  If you have any doubt about what annoys you, ask your family who will have no trouble providing you with a full list of your mental buttons and the best way to push them.