Time to dig into the material. For this task, I suggest reading through The Ethics at least once, then re-reading it (while making essential notes). Once you reconstruct the main ideas you can join in on the discussions and contribute what you found most relevant or interesting. 

I should mention that each of the thirteen chapters is meant to advance a single argument; that the end of human life is happiness (eudaimonia, sometimes translated as a floroushing, or supremely blessed life). This is important since it may be assumed that the work, owing to its status as a collection of lecture notes, is incomplete, or lacking a coherent line of reasoning. However, I would strongly recommend reading The Ethics with the assumption that there is in fact an intelligent structure behind the text. I think Aristotle's views will come through most clearly if we set ourselves up to understand what he has to say in a charitable frame of mind.