|I first learned this tip from Linda Stewart of PACC, but it is so helpful I wanted to pass it on.
When sewing the sequined knit fabric - you know the stuff, the knit fabric that has the mylar dots glued on it - take some waxed paper, cut it into strips, lay it over the fabric and sew. Without the waxed paper you end up with glue all over the needle. When I was altering a skating costume for my friend's daughter, I had to clean the needle about every 5 minutes - and that was using a titanium needle, which is supposed to prevent gunking up. But with the waxed paper, it "wipes the needle off" as you sew. When you are finished, just tear away the paper. It works like a dream!