Comforter sets would be packed in an individual pvc bag ( the contents it contains would be as per your request). And the quilt cover could be made of different material like 100% cotton from 180 thread count to 1000 thread count, 100% polyester from 65gsm to 95gsm (oe even 120gsm if you need), polycotton, peachy fabric, etc., and the fillings are usually 100% polyester.
And the colors are wonderful and could be printed as per your designs.