With Fall just around the corner and the weather about to cool, September is probably a good time to start taking cuttings of your plants for next year.
Air-wrapping was shown to me by the most knowledgeable old gardener I know while still living in FL. She initally showed it to me on roses, but said it has worked on fruit trees (and had the proof in a pot right there), flowering shrubs and various other plants.
What you need:
Sharp, CLEAN knife
Bucket of water
plastic wrap & wire ties
Drop your moss into the bucket to start soaking. Choose a section of stem that has last Spring's growth on it (not brand new growth, must be a little older, but not so old as to be woody). Take your knife and gently score around the branch, and again about an inch/inch and a half below your first cut. Gently peel the bark/outer skin off all the way around that 1" slice.
Take a handful of the wet moss, squeeze it gently - you want it wet but not dripping - and wrap it fully around the cut. Wrap the moss gently in place with tinfoil (my preference, since I don't have to use ties) or the plastic wrap.
Occasionally check the moss to ensure it is still damp. In a month to 6 weeks, there should be enough root developed that you may cut the branch free from the parent, and set it into potting soil.
(it's kind of like layering, only it's done above ground - I've found this works on Rose of Sharon & Crepe Myrtle, neither of which you're going to get a branch in the ground from!)