I love Jimmy Diresta’s making videos: they are rough and ready approaches to a task but are also tightly edited, include clever techniques, and (most importantly) can be watched with the sound turned off without bothering those around me.
He recently posted an excellent video on making a molded leather knife sheath for a Leatherman + accessories. The techniques in this video can easily be adapted to making any small molded leather container.
Worth a watch: https://www.youtube.com/watch?v=VAXInoK2fls
One thing I personally would have done differently would be to make the belt loop top be inverted on the back (making an upside-down “J” rather than an “I” in profile): this would make inserting the belt easier for virtually no additional effort.