I would recommend getting at least a dozen or two dives in.
Before you take AOW, the most important thing you should have down is buoyancy. Next skill is to be calm and relaxed (ie. no hand waving and flailing).
I did my AOW dives last weekend with a woman....that I wanted to kill after the class. We did a photography dive - I could take pictures of anything, because every time I stopped to get close to a fish, her fins were stirring around in the bottom like a blender. It was BAD!!
During our deep dive, our instructor had to constantly add air to her BC on the way down, and dump it on the way up. She just did not get it! I would like to note, I don't want to get into the argument that "the instructor should have spent more time, should have done this...blah, blah, blah".
During navigation, she didn't "get" a compass. I had to show her about half a dozen times that you need to hold the compass level - not tilt it completely vertical so you can see it!
And don't even get me started about our search and recovery dive....I finally said screw it and just went and did the tasks by myself and ignored where she was. Yes, I know this was not the "right" thing to do...but if she can't have the basic skill to follow behind me and stay off the bottom while I am doing something as simple as sweeps, she should not have been in the class!
Take you AOW class when you feel you're ready - just make sure that you have your important skills down before you do it - you will get more out of the class if you do, and your dive partner and instructor will appreciate it. AOW class is not the time to practice buoyancy - you should have that down before you even sign up for the class.
But most of all...have fun!! Even with the dive partner I had, the class was an absolute blast! Search and recovery was very cool - as a matter of fact, I'm lucky enough to get to do a search & recover dive tomorrow in black water and I can't wait!!