I was teasing a fellow seamstress friend of mine for not knowing the purpose of the strawberry part of a tomato pincushion. (It's filled with sand. You push your pins into it to clean off any burrs.) Well, here's one of those things I should have learned a long time ago. (Hmmm, how many years have I been sewing... Never mind!)
I was looking at the instruction manual for one of my sewing machines that I don't use very often. I happened to look at the page on how to wind the bobbin. Wow, I never knew that you're supposed to thread the thread through that little slot before winding. All this time I've been carefully trying to pre-wind some thread onto the bobbin to keep it from sliding out, especially with rayon threads.
Threading through the slot first works so much better. You just hold onto that tail as it starts to wind. Once started, clip off the tail and you're good to sew!