Just a guess but I found that shows the fabric being thread through the foot.
http://www.cutexsewingsupplies.com/p...e-presser-foot I'm guessing that it is somewhat similar to a binder in that the fabric goes through and keeps the stitches an even distance from the edge. The above site also shows which machines it fits. Maybe one of them has instructions on how to use it. I do see that there are some Singer machines listed. Maybe you could find a manual at singerco.com
Janey - Neat people never make the exciting discoveries I do.