The trick to surviving is to stay in the middle as long as you can, and when you are forced to a side, always favor the corner where the bishop can't touch you.

Right. But remember, if the stronger side plays correctly, he can force mate. However, he doesn't have a huge margin for error with the 50-move rule.

K,B, N vs. K:
The trick is to force the King into a corner square as the same color as the Bishop. Not as hard as you think.
When someone does not know what to do, the trick is for the lone King to go to a square opposite of the color of the Opposition Bishop. And stall until the 50 moves are up.
The best way to set up the pieces and practice until you get right.
If you do not have a partner then go to Nabisco.com a weak chess program, but it allows you to promote a pawn to any piece. Many online programs do not. Or AOL chess, probably a 1200 strength program, and get the game where you have a K, B, N, vs. the lone King.
I tell kids when I teach in the summer to practice the ending.
That is always the key practice.