If you prefer to make your own pet bed, Walmart carries a line of Do-It-Yourself Pet Bed Kits, which encourages recycling and reuse of old fabrics and linens or whatever you want to put inside the duvet to make it more comfortable. This kit is:

100% cotton, fully-zippered
Stylish and modern
Easy to clean and maintain
Durable, washable, and pre-shrunk
Model: 9400218
Size: Small
22in x 27in for small dog or cat
Reduce, reuse, recycle

Via Walmart