Inexpensive, compact, lightweight, easy to set the magnetic declination (if you don't know what that is, it's urgent that you do some research!) and works well with a map--Silva Starter Compass.

My one experience with a button compass ended when it reversed polarity while I was riding a Swiss electric train. When I reached Grindelwald and started trying to navigate to the hostel, I discovered that the sun was setting in the east!