What is with the attitude about being important enough to have to hide? Didn't you play hide and seek or cowboys and indians as a kid. As was said earlier, hiding can be fun. Anyhow, the question is legitimate and worthwhile. The better you know how to go undetected, the better you understand how to search. You don't have to be "important" to be looked for.
As to the question, good sense is your best bet. Pay attention to your surroundings and blend in. The previous suggestions are all great, try some, like playing grown-up hide and seek.
As far as books, you can check out "The Complete Tracker" by McDougall, "Tracking & The Art of Seeing" by Rezendes and some of the best literature on hiding can be found in the U.S. Army manual listed earlier and most of the Sniper Training Manuals put out by U.S. Army and Marines. But, nothing beats good ol' woodscraft and smarts.