The most basic form of meditation focuses on breathing. Breathing can also be used in a more intermediate fashion. Take your normal stance for meditation: back supported either by a chair, a wall, or sit cross-legged; eyes closed, muscles relaxed. Clear your mind of any sort of extraneous thought. Forget the traffic you sat through during the day, the stress of work, or any personal relationship. Instead, put all your attention on your breathing. This simple action is relaxing and proves meditation already a success, but you can take it one step farther!
As you breathe in, say to yourself, "This is an in-breath." When you exhale say to yourself, "This is an out-breath." Repeat this every time you complete a cycle of breathing. The exercise sounds simple, but our brains are conditioned to think constantly in the modern world. You might find yourself having trouble maintaining the mantras for a sustained period.
If you cannot continuously focus on your breathing in this manner, take a moment to regroup and begin again. The act of calling out your breathing to yourself will help you achieve two things. The first is that while you tell yourself "this is an in-breath" and "this is an out-breath" your mind will begin to notice your breathing instead of what you will be fixing for dinner in an hour. Secondly, and most importantly, by focusing on your breathing in this manner you will start to feel the rhythms of your body. Respiration is involuntary, but vital to life.
Our lungs bring air into our bodies and expel carbon dioxide dozens of times per minute, yet we quickly forget that they are even working. Paying attention to your breathing will introduce you to a part of yourself that is often overshadowed in today's loud world. At the simplest level of description, you will be listening and honoring your body for living! The true magic of this method - magic in the connotative sense, of course - is that if you truly focus completely on your breathing, your mind will clear of the problems that inhabited it only minutes before and you will notice a sense of relaxation you probably thought could not occur in your body. All you will be doing is being, something your body desperately needs for relaxation!