How to remove 89 corolla compressor belt?

Hello! I'm a novice in the car maintenance arena. In fact, I don't even change my own oil. I've decided to try to change the belts on my 89 corolla, and I'm one third of the way there. I've gotten to the air conditioner compressor belt, and I can't figure out how to loosen the tension to remove the belt. The manual I'm using is not very specific. There seem to be 2 nuts that could be adjusted. Can someone help out a beginner? Thanks!

Jay