Please, note that the option to take a screenshot may vary on different iOS devices. The basic steps to take a screenshot are as follows:
- Press and hold the Top or Side button.
- Immediately click the Home button, then release the Top or Side buttons.
- A thumbnail of your screenshot appears in the lower-left corner of your device. Tap the thumbnail to add drawings and text with Markup, or press and hold the thumbnail to share the screenshot. Swipe left on the thumbnail to dismiss it.
To find the screenshot you just took, along with ones you've taken before, go to Photos > Albums and tap Screenshots.
For more information on taking a screenshot, please, follow the link.