How to Reformat Android Phone
Back up data and movies/photos on the device
Click the image button ⋮⋮⋮ to open the Applications Manager application manager.
Scroll down and tap Photos with the multicolored pinwheel icon.
Tap the ≡ -shaped button in the upper-left corner of the screen.
Tap the Settings option in the middle of the menu.
Tap the Back up & sync action at the top of the menu.
Swipe the "Back up & sync" button to the "On" position. The slider will turn blue.
Press the Home button.
Open your device's Settings. Apps usually have a gear icon (⚙️) or a frame containing multiple sliders.
Scroll down and tap Accounts located in the "Personal" section of the menu.
Tap the Google entry . The list of accounts is listed in alphabetical order.
Swipe the slider to the "On" position. Slide the buttons next to the data you want to back up to the "On" position. The switch will turn blue.
Turn on Drive to sync photos.
Tap the button next to the buttons you just swiped to the "On" position. Click each button in the menu to start syncing instantly.
You can reload apps that were previously installed when you sign in to your Google account on the reformatted device.