Play or pause music:
click once on the earbuds touch area (both left and right are ok)
Next:
Three clicks on the left earphone touch area
Previous:
Three clicks on the right earphone touch area
Volume + :
Double-click the left earphone touch area
Volume - :
Double-click the right earphone touch area
Answer a call:
Click the touch area of the earbud (both left and right are ok)
Rejecting a call:
Long press the touch area of the earbud for 1.5 seconds (both left and right are ok)