Here in Pennsylvania most wear their rings on the right hand due to the manner in which our hands were placed while receiving the first degree… and probably even more likely due to the fact that most masons are married men, and as such, already have a ring on the left hand.
There is no consensus, at least in PA lodges, as to whether the points of the compasses should face the wearer or the observer. A few will say that they should face the wearer, replicating the first thing he observed in the lodge when he got the first degree (the compasses and square on the Bible), and thus having great spiritual meaning as well as serving as a reminder to the brother of the lessons he learned in the degrees whenever he looks at his ring. Having tried wearing the ring with the compass points up, I soon grew tired of people asking “what’s that?” and now wear rings so that they are right-side-up and recognizable to the observer.
The ring finger is most popular,at least in my circles, though the pinky ring is a close second. The pinky ring is also less likely to cause pain when you shake hands with a non-mason who grips you tight enough to crush walnuts. (You definately learn the finer points of shaking hands in this fraternity!)