Wearing
Adjust the slider to the preferred length.
In order to hear the best quality sound, be sure that the ear pads correctly cover both the left and right ears. If there are gaps between your ears and the headphone ear pads, sound will leak and the bass level and effectiveness of the noise cancelling function will be reduced.
NOTE
Be careful not to trap your fingers, etc. in the moving parts.
Do not pull the slider too forcefully.