1. Commit to just 2 minutes a day. Start simply if you want the habit to stick. You can do it for 5 minutes if you feel good about it, but all you’re committing to is 2 minutes each day.
2. Pick a time and trigger. Not an exact time of day, but a general time, like morning when you wake up, or during your lunch hour. The trigger should be something you already do regularly, like drink your first cup of coffee, brush your teeth, have lunch, or arrive home in the evening.
3. Find a quiet spot. Some like to meditate in their own room; others prefer to find a spot in a park or some other soothing setting. It really doesn’t matter where — as long as you can sit without being interrupted for a few minutes.
4. Sit comfortably and focus on your breath. As you breathe in, follow your breath in through your nostrils, then into your throat, then into your lungs and belly. Sit straight, keep your eyes open but looking at the ground and with a soft focus. If you want to close your eyes, that’s fine. As you breathe out, follow your breath out back into the world. If it helps, count … one breath in, two breath out, three breath in, four breath out … when you get to 10, start over. If you lose track, start over. If you find your mind wandering (and you will), just pay attention to your mind wandering, then bring it gently back to your breath. Repeat this process for the few minutes you meditate. You won’t be very good at it at first, most likely, but you’ll get better with practice.
Source: http://zenhabits.net/fundameditate/ (abridged)