Instructions
For the latest and most accurate information regarding how to take a screenshot on your iPhone, please visit Apple's support website at https://support.apple.com/en-us/102616.
Outcome
Your screen will display a white flash for approximately one second to indicate that the screenshot was captured. Inside the Photos app, the screenshot is added to the "Library" tab, and it can also be viewed in the "Screenshots" album. From there, you can share it with a support representative, if needed.