I've had a couple of people comment on my sewing holster (post here). The pattern comes from Inspired to Quilt by Melanie Testa (available from Amazon and probably a dozen other places, including the library, where I got it).
The basic set up is: quilt one long thin rectangle (5x42"); quilt two pockets (5x8", folded so the fold forms the top edge of the pocket); sack quilt one 5 x 7" (also folded) to form the pin holder. The pin holder has a magnet put in it (check its the right way around :-) before you quilt it. Then cut the neck and pocket patterns out of the quilted pieces.
The main piece has a long straight edge; the other edge is narrow around the back of your neck and curves out towards the ends. The ends are rounded. The pockets are shaped to fit the ends. The pin holder is shaped on an angle to fit nicely on the shaped neck piece. The unseamed edge of the pin holder is the one that attaches to the neck piece. The whole thing is bound, and the pockets are bound into it. A slightly smaller piece of felt is sewn under the pin holder.
I don't want to put the pattern on line 'cause it's not my copyright. I'm guessing if you're clever you can probably make one to your own design, or hunt for the book at your local library.