Mindful body scan meditation is a wonderful way to be aware of different regions of the body, and allows you to experience how each part feels, without trying to change anything. It helps you get in touch with your body, to let go of feelings of needing to get things done, and release pent-up emotions. And just like other forms of meditations it helps to train attention.
It is an investigation into the moment-to-moment experiences of the body. By bringing awareness and acknowledgment to whatever you feel or sense in the body, the body scan can be very helpful in working with stress, anxiety, and physical pain. The body has it's own specific way of talking and of keeping record of any physical, mental or emotional stress or ailments and if you don't take a moment to listen, you more than likely will be missing a lot of what it is trying to say to you!
You can practice mindful body scanning laying on the floor, a mat or a bed. You can begin by focusing your attention at the top of your head and then move down the body. It’s good to start with a guided practice to get used to how to practice (you can find free videos/audios on youtube).
Don't worry if you fall asleep during your body scan practice. When you realize you’ve been nodding off, take a deep breath to help you reawaken and even try repositioning your body (which will also help wake it up). When you’re ready, return your attention to the part of the body you last remember focusing on.