Unlike vibrato on the flute or violin, vibrato on the Saxophone requires the use of one’s jaw to create the wah wah sounds.
Take your hand and place it under your chin- and say Wah wah wah wah etc (to feel the motion that your jaw will be making when you are playing vibrato).
Everything else stays the same- your embouchure, throat position and air (the jaw just moves up and down (wah wah wah etc).
Practice the vibrato with a metronome 🙂
To listen to different variations of vibrato-
- Johnny Hodges (Deep’s blue- fast and wide vibrato)
- Cannonball Adderly- Stars fell on Alabama- Fast and narrow vibrato
- Dexter Gordon- Guess I’ll hang my tears out to dry- Slow and wide vibrato
Reference:
Alto Saxophone basics 