I hate urinals; I never use them. I'll always use a stall (standing up) unless it's some sort of emergency, and in that case I'll just cut out the middle man and piss right on a tree or rock or wall or something. Urinals are gross and primitive; uncivilized. That said, there's quite a bit of etiquette involved in using a urinal, particularly if there are other men already in the midst of doing their business. Here's a handy urinal tutorial to teach you the basics; it may be of particular interest to women, who probably don't have a great deal of experience pissing into a trough.