iOS (iPhone or iPad)

Press and hold the 'On/Off' button with the 'Home' button for a second till the screen flashes, alternatively press and hold the 'Volume' button with the 'Power' button for a second till the screen flashes. The screenshot will be saved automatically under 'Photos'

Android

The instructions vary between the different devices in the market, here are the basics: Press and hold the 'Volume' button with the 'Power' button for a second till the screen flashes. The screenshot will be saved automatically inside the 'Gallery' under the 'Screenshots' folder.

Mac (desktop)

Hold down 'command, shift and 3' on the keyboard. The screenshot will be automatically saved on your desktop.

Windows (desktop)

Press 'PrtScn' on your keyboard, alternatively hold down the windows icon button and click the 'PrtScn' button. The screenshot will be copied to an invisible clipboard, alternatively be saved inside the 'Pictures' folder under 'Screenshots'. Now open a new Word document or Paint and hold 'Ctrl' and 'V' to paste the screenshot.