Loc: Bay Area, California, USA
In the right weather you can really give your compass a workout. I was on a local mountain and it was a complete fog-out, unable to see more than about 20 feet sometimes. I felt pretty weird not knowing which way was north!
Learn to use it, then go out in heavy fog <img src="/forums/images/graemlins/grin.gif" alt="" /> close to home <img src="/forums/images/graemlins/wink.gif" alt="" />
One suggestion: Before you study the specifics of a map and compass, study some physics and physical geography. Learn (relearn) how the magnetic fields of the earth work. Once you have a grasp on that it's much easier to understand why a compass works, especially with declination.
As with most endeavors, learn concepts before specifics.
Try "Be Expert With Map and Compass" by Bjorn Kellstrom. He invented the protractor (Silva) compass and literally "wrote the book" on its use.
If, on the off chance, you have a military style lensatic compass you'll be better off using a military manual for understanding the exact use of it, though Kellstrom's book is still a great guide for common orienteering problems.
"There are no comfortable backpacks. Some are just less uncomfortable than others."