Valveless scale exercise
So-called valveless scales can be found in several methode-books.
In "ASA-methode" by Rolf Quinque (Editions BIM, Suisse) he uses this
technique as preparatory exercises for high register training. A similar
study can be found in "The Art of Art Farmer", (Charles Colin, New York).
In these two books the exercises start on c2. For a beginner this can be too
high and strenous. By starting an octave lower, on c1, and developing that first,
it will be easier to finally play from c2.
(Note: This routine is based on a James Stamp exercise.)
Play it legato and with normal fingering first. Then repeat several times with no valves.
Slowly at first.
When the exercise (Phase 1) becomes easy to play, start the pattern from g1 (g1 - d2).
When you can play Phase 2, finally start from c2 (c2 - g2).
This exercise can of course be played with the lips only and on the mouthpiece.
Note: Do not practise this too long. If you feel stiff, use some pedal-exercises
to relax the facial muscles. You could use an "opposite" pedal-exercise, where you
play a scale from low C down to pedal C "valvless" (only with open fingering),
or you could use this Warmdown excercise.