To Power On
Press and hold the power button for 1 second to turn the Pi SOLO on. Once it’s finished booting up, you will hear a chime, and the light will stop flashing and turns into a solid green.
To Take Photo
To take a photo, tap the power button, you will hear a shutter sound when the photo is taken.
To Take Video
Press and hold the power button for 1 second, to switch to video recording. You will hear a ring. Recording will start with a second ring , when you release the power button. To stop recording, tap the power button.
To Power Off
Press and hold the power button until the light turns off. You will hear a chime when the system shuts down.
Or watch video tutorial: https://youtu.be/j1QRk95MVEM