How to send text messages when Xiaomi 2' s mobile phone is powered off?

Go directly to the SMS interface, click below to send SMS, enter the recipient's mobile phone number or look it up in the contacts. There is a+sign on the left of the text message input box below. Click in, select "Pictures", enter your "Gallery", find the "Local Pictures" folder, click in to find the screenshot you want to send, click OK to insert the screenshot into the text message, and then click.