When you want to temporarily suspend the operation of the Colibri (for example, to watch a video or read a text without the pointer movement interfering), repeatedly nod your head horizontally (making a “no” gesture) until you hear a beep.
Notice that from now on, the pointer will not move when you move your head, and the Colibri will no longer emit beeps and mouse clicks.
To reactivate the Colibri, making it control the pointer and clicks again, make vertical movements with your head (making a “yes” gesture) until the cursor starts moving again.