Before you power on your gimbal, you will want to have your camera mounted on. Powering on the gimbal without a camera installed can damage the unit. Please take a look at our article, "Mounting Camera" for instructions on how to do this.
Once you are ready to power on your gimbal, simply press and hold the power button for 3-4 seconds until you see the amber light turn solid. This will automatically turn on the unit and activate the motors.
The gimbal does have a Standby Mode to help you conserve some battery life as you prepare for your next video/image capture. In order to get to Standby Mode, you will simply want to disengage the motors by pressing and holding the Mode button for 3-4 seconds. You can re-engage the motors again by doing the exact same thing, pressing and holding the Mode button for 3-4 seconds.