The vintage doll bed was an empty metal frame when I found it at a flea market. First, I spray painted over the rusty white. Then, I made the bedding from sheets purchased at the Goodwill. The mattress was a piece of foam from a former mattress pad stored in my attic. So, what does this have to do with sweaters? Well, look closely.
The foam is covered in an old sweater!
I knew the fabric from the old sheets wouldn't really cover the yellow memory-foam very well (as it wasn't exactly a high threadcount!). So, I took a very soft acrylic sweater and stitched it into a pillow case of sorts. The foam went in, and then I stitched the dust ruffle around. The problem came when I put the mattress in and realized that this is more of a crib then a bed so I will have to make some adjustments.
I seem to recall making a similar mistake when sewing a dust ruffle for my daughter's crib twelve years ago. I guess we never learn!