http://blog.swimator.com/2011/09/how-to-relax-in-water-sink-to-float-and.html
You can also get more swim tips on your Android device here:
https://play.google.com/store/apps/details?id=com.swimator.facebook
The number one problem and an obstacle in learning to swim or progressing forward in swimming skills is the tension in swimmer's body. Learning to relax and trust the buoyancy of swimmer's body in the water is a skill to master in order to swim well in the future.
If you wonder how to plug your nose with natural nose plug - read this: http://blog.swimator.com/2011/07/human-nose-clip-getting-water-up-my.html
more swimming tips: http://blog.swimator.com or http://360swim.com/fb