A popular question that keeps coming back is how to take a screenshot.
How to do this can differ between models and firmware version but there are two different methods used in Xperia devices.
Press and hold the on/off button. This will bring up the options window you see below. Tap Take screenshot to capture your screen.
This can be done while in any application or menu of the Sony LT26I-BK.
Press and hold both on/off and volume down (-) key at the same time for about 2 seconds and the phone will take a screenshot of the present screen.
I hope the video below can help you Take A Screenshot on Sony LT26I-BK:
It still does not work:
On most devices you need Android 4.0 or later. However, you could try using an app instead.