I have had a lot of luck propagating AV's by just dipping a leaf in rooting hormone, sticking it in a pot of regular potting soil, watering thoroughly, and then sticking the pot in a Zip-Lock Baggie. It needs some light. I've put the baggies in both an eastern and southern exposure and have enjoyed equal success rates. I'm thinking it takes about 2 months to see the new plantlets.

This has even worked for me in less-than-ideal situations, as when the cat has chewed off a leaf and I find it a day or two later. Fairly fool proof.