Use a consistent Left Hand Grip
Brass players will use many combinations of left hand grips, especially where they place the gripping fingers. Please note that THE LEFT HAND IS THE ONLY HAND THAT SUPPORTS THE INSTRUMENT [ASSUMING THE PLAYER IS RIGHT-HANDED, THAT IS] AND THE RIGHT HAND IS USED ONLY TO MANIPULATE THE VALVES OR SLIDE AS THE CASE MAY BE.
This is an important point and not to be taken lightly. Even the technique of manipulating the trumpet's 1st and 3rd valve slides can be developed into an art without losing the left hand grip.
The point here is that no matter what method one uses for the left hand and fingers, IT MUST BE CONSISTENT THROUGHOUT ALL PLAYING.
The left hand grip is the guardian of the embouchure formation.
Since we all are teachers, whether ultimately "our own teacher", teaching others privately or teaching the youth in a school setting such as Middle School, High School or College level, I will be gearing FixYourBrass to include teachers and performers. My posts will have various "topics" (Range, for example), with information for development and maintaining these categories as well as problems that may arise. The posts may be followed by my own "comments" and as to solutions to these problems watch for follow-up posts. So please add your own comments as to create a dialogue regarding said posts as well as any "personal problems" that I can help with. Looking forward to this exchange.