Cynthia a wing band is simply a little metal clip, kind of like the ones that clip the toes of some socks together in packages? Seen them?
Anyways they have numbers on them, mine just come in random numbers but some can be made to order with what you want on them. My wing bands are pretty small, size 3 I think, and are the Jiffy brand.
I had to order a special applicator for the, looks like a single hand hole punch, with a special grove for the wing band to fit in. You simply put the wing web between the "c" and then pinch together. Took a bit of practice to get the metal tab lined up in the right spot to "lock" the band on, but once on they seem to work well.
I banded all my BLRW from Islandgirl this spring, they were about3-4 weeks old. I have tried day old but not much there for wing webs, so best to ID them with leg bands and wait till 3-4 weeks to do them.
I will be doing wing bands and then leg bands as well for most of my birds, the leg bands for the non feathered legs and as a visual indicator, the wing bands will be for permanent ID.
I have heard stories of birds getting the bands caught, but I thin if they are tight enough to the web that shouldnt happen, just remember doing young birds to leave some gap for growth. But if doing adults make them flush.