I have had several requests for info on how to sew on a sturdy button. I have searched you tube and found the following:
Here is a Brit lady showing the proper way to sew on a flat button. If your thread gets kinky, use beeswax on the thread. The little shank that is created by wrapping the thread around gives space for buttoning thick fabrics, and just makes buttoning a flat button easier. Using a toothpick works great.
Another version of sewing on a flat button. Very well done.
Here is a way to sew on shank buttons - like our uniform buttons
One of my tricks is to use a drop of Fray Check on the threads. This product is available at all sewing stores. It is a bit stinky until it dries.