This is the way I do the 6 mouthpiece exercises every day. It is the very first thing I do in the morning. It only takes 7 minutes and creates a perfect feel for the following trombone playing/practice/routine.

The recording is not nearly perfect, or something that should be taken as ideal. It is just a one take normal morning routine.
However, focus as much as possible to be as close as you can to perfect pitch and timing. Excellence is not an act, is a habit.

The mouthpiece is a perfect practice tool for cleaning the sound, building range, and nonetheless articulation.
As you saw, I also 'freebuzz', and also use the 'Inspiron' breathing device which I find extremely helpful in visualizing my airflow.

Visit my website https://alexandrumoraru.net/ for more exercises, routines, and maybe some inspiration.