• How do you play the trumpet?  Sound is produced on the trumpet when the player energizes the air molecules already in the trumpet by blowing into the trumpet with the intention of making a sound.  The energy traveling in the air sets the air molecules already inside the trumpet in motion. They “reflect” of the atmospheric air at the bell, and a standing wave is created in the trumpet (concept borrowed from John Harbaugh,  
• https://www.youtube.com/watch?v=MVs2G60-ilo&t=466s).  The lips sympathetically vibrate with this standing wave in the trumpet, creating a tone.  The lips will naturally come together when air is blown through the trumpet (Bernoulli effect).   
• Therefore, the enrgy in the air and the ear plays the trumpet.  You do not need to buzz your lips.  In fact, doing so will cause problems.  I discourage lip and mouthpiece buzzing for this reason.
• Breathe as naturally as possible.  Lay down and observe how you breathe in this position.  The abdomen should rise on the inbreath and fall on the outbreath.  When standing, the gut should relax on the inbreath, and the chest should rise and expand on the outbreath.  Then, let the music teach the body how to breathe.
• You do not need to use a lot of air to play the trumpet.  Too much air will cause problems.  You need just enough to touch and vibrate the air already in the trumpet.  This is very little.  You do however need air that moves.   
• Cut normal drinking straws to about 6 inches in length.  Students can practice blowing through an open straw. If they block the open end of the straw by closing it off with their finger, they can produce a pitch/tone by blowing into the straw.  This is akin to producing sound on the trumpet. You should not feel the air coming back towards you.  If you do, you may be using too much air. Transfer this feeling and sound of resonating the pipe to trumpet playing (exercise could be misunderstood in writing, better to demonstrate in person; exercise borrowed from MWNA program designed to retrain brass players:  https://musicianswellness.com/).
• The teacher should encourage the student to focus on feeling the air travel freely through the pipe and hearing how they want to sound.  This external focus of attention will be a far more successful method of motor skill development than teaching the specific motor skills themselves (based on research by Gabriele Wulf, http://gwulf.faculty.unlv.edu/).  
• The teacher can however correct bad physical habits that present in their students.  Otherwise, teach by having the student envision the sound they want.  While demonstrating is helpful, description, recordings, and the student’s imagination are just as helpful.       
• Many trumpet playing struggles can be addressed focusing on the above concepts.   

Concepts borrowed from MWNA program designed to retrain brass players:  https://musicianswellness.com/.