Building a Retaining Wall

I've got a steep slope in my backyard and I'm concerned about erosion, so I'm going to build a short retaining wall this afternoon. I've read directions several times but I've never done it before, so it should be a challenge. Assuming it goes well, I need to build another wall on the same slope for a terrace effect, and that should considerably slow the erosion. Wish me luck!

Update:

Mission accomplished! Pictures to follow, when I find my camera.

Update 2:

Pictures after the jump!