New Bee M50 Manuel D'instructions page 5

V. WEARING ADJUSTMENT
(1) Slide the headset from above your ear to behind, and then lightly
press it toward the ear; before putting on the headphones, take off your
glasses first, so that you can adjust to the most comfortable state for
wearing.
(2) Rotate the microphone boom to make the microphone toward your
mouth.
(3) Adjust the microphone up and down to find a more suitable position.
(4) If you want to change another ear to wear the headset, rotate the
microphone boom upwards and twist, make the earbud turn to another
side, and then lower down the microphone boom.