Storage:
Collected cuttings...
Cut to approximately 9" long, with the bottom cut just below the bottom node, then place in 1 gallon Permanent Marker labeled Ziploc Freezer bags with 2 tablespoons of dry shredded long fibered sphagnum moss. Then into the crisper drawer in the refrigerator.
Purchased cuttings...
Unpack and unwrap the cuttings and place in 1 gallon Permanent Marker labeled Ziploc Freezer bags with 2 tablespoons of dry shredded long fibered sphagnum moss. Then into the crisper drawer in the refrigerator.
Long term storage...
Dip both ends of the cuttings in melted Tea Candle wax, put back in the zip lock bags and place in the refrigerator.


Rooting:
In Long Fibered Sphagnum Moss...
Place several hand fulls of lightly damp Long Fibered Sphagnum moss in the Zip lock bags with no more than 1 dozen cuttings, that are individually labeled with an Elmer's Paint marker, in each 1 gallon bag. Then place the bags in a dark closet at about 75 deg F. Check every two days and inflate bag. If any mold growth, wipe cutting with paper towel and spray with peroxide solution (1 part 3% Hydrogen peroxide/3 parts water).
In Seedling Tray...
Cut to 7"-8" maximum to fit under the 7-1/4" high humidity dome. Fill the plugs with pre watered Coir Based seed starting mix, insert cuttings, that are individually labeled with an Elmer's Paint Marker, and compress the mix to hold the cuttings in place.  Then place the trays in a dark closet at about 75 deg F. Check every day and mist all the cuttings with water. If any mold growth develops, wipe cutting with paper towel and mist all the cuttings once with peroxide solution (1 part 3% Hydrogen peroxide/3 parts water).
In General...
Whether using Moss or Plug trays the top cut ends of the cuttings are always sealed with wax (toilet bowl seal wax is used for sealing newly cut top ends when rooting). If Rooting Hormone is used, it is applied to the bottom cut end only.

eboone:

I use flagging tape to label different varieties in the same box. Write on it with a permanent marker and tie it around an inter-nodal space closer to the top than the bottom.

Some boxes only have one variety, so just label one piece of tape and lay on top of moss.

A consideration when putting multiple varieties in the same box in layers: They all most likely will not root at the same time. If you go in to retrieve the rooted ones, it's easy to damage those which may need more time. Not saying you can't do it, just be careful. The same can be said  when rooting just one variety and you have a mixture of week tip cuttings and nice fat hardened cuttings, or for that matter cuttings from different trees. I just finished my first round of cuttings and potted out of some boxes (mixed varieties) 3 times over a period of two weeks. Running about 95% rooting. Appears that I am losing a few of the thinner tip cuttings (purchased ones) in the SIPs. Did another head count today and looks like I will still achieve around 90%.