A got this idea from a craft show, they were selling filled for $18.00. I spent $3.00 for the suet feeder, bought at our grocery store.
Inside are pieces of yarn and stripes cut from a holey wool sock. I was thinking I could have also cut up an old sweater. You could even buy a cheap skein of yarn.
Per the craft show, the birds like to pick through for the pieces that are appealing to them.