Originally Posted by catrancher
I would just put it in the envelope. I usually use padded envelopes, however. They seem sturdier to me.
For fabric I prefer to use the padded envelopes or the tyvek ones. Wrapping your fabric in plastic is a good thing. And be sure to put a copy of the TO and FROM addresses inside the bag with the fabric. If the envelope gets destroyed or wet, the address is still preserved inside.
EDITED TO ADD - Fabric can get really heavy for mailing. I think that most of us use the Flat Rate envelopes from USPS for more than just a bit of fabric.