Coworker Connie asked if I could repair her favorite bracelet for her. The string had broken. It had one of those sliding knotted clasps. I told her that I really didn't know how to do fix it, but I had always wondered how that clasp thing worked. I told her I would give it a try. This weekend I studied several YouTube videos. It turns out that the string that's used for the clasp is totally separate from the string that you use to connect the beads. All you do is make square knots and then glue the end.
These are the two videos that helped me the most. I tried both methods and ended up using the first one.