How to take a screen shot/capture on Android phones
To take a screenshot on Android 4.0 and above press and hold your smartphone’s power and volume down button at the same time for 1- to 2 seconds. You should then hear a shutter noise and the screen will flash; the screenshot will be saved to your photos gallery; there will also be a screenshot notification in the drop-down notification bar from which you can access your screenshot.
On some phones, such as the Samsung Galaxy S3, S4 and S5, you will instead need to combine the volume down button with the Home button.
On some phones, such as Sony, the ‘Take a screenshot’ option is available from the Power off menu. Press and hold the power button for 1 to 2 seconds until the power options screen appears. If the option is available select ‘Take a Screenshot’.