|How long should it take one reasonably intelligent (?) woman to figure out how to use safety pins? After years of losing track of what kind(s) of interfacing I have, I started using sticky labels to mark each interfacing with the manufacturer, name, fiber content, etc., only to carelessly cut off the label and lose it at some point. Now I write on the sticky label, then fold it in half (sticky sides in) and attach it to the interfacing with a safety pin that can be moved as I use up the interfacing. (Duh!) I mark another large safety pin with the same label, and use the large pin to collect scraps of the appropriate interfacing. Now I have a source for small pieces of interfacing so I can test it on a fabric before I commit to cutting into the big piece, and the labels make it easy to find the right interfacing.