I have never understood what does the exercise involve? Can you please tell me what is it that you "do" in those five minutes that you meditate? I want to try this. Thanks.
There are many ways to do meditation (and many goals) but generally in silent meditation you pay attention to what your mind is doing, how you are feeling emotionally and physically, etc. To have a "reference point" you can pay attention to your breath.
Jean Smith has a really great, concise book that outlines what to "do" if you're just starting out with meditation. It's called "The Beginner's Guide to Zen Buddhism" and is absolutely great for beginners.
It's not the end-all-be-all book for meditation (or Buddhism) but it is a good starting place I think.
http://www.audiodharma.org/series/1/talk/1762/ is a good, free introduction (this is from a Buddhist center, but the podcast applies to mindfulness in general).