Mindful Breathing  

Mindful Breathing is the most basic breathing meditation. With this technique, you simply focus your attention on your breath, the inhale and exhale. You can do this while standing, but ideally you'll be sitting or even lying in a comfortable position.

Here is a video to help you get started: R. Murali Krishna, M.D.’s "Live Life Well" video series: Present Moment Awareness

If you have an Apple watch, the Apple Breathe exercise on the Apple watch is a form of mindful breathing.