Bells up
Raising the bell into the air. Notated with a verbal instruction. Very
striking when done by the whole horn section together, but primarily
a theatrical effect.
Bells up:

Glissando
A slide in pitch between notes. Valve/lip
glissando involves hitting as many harmonics as possible between two
pitches. This is the standard glissando, but it is also possible to
use the hand to slide a semitone.
Horn Glissandi
Glissando:
Hand glissando:

Trills
Semitone
trills work anywhere on the instrument. Whole tone trills can be more
difficult, especially in the low to middle register. Lip trills between
two harmonics work well in the upper and middle registers.
Trills:

