The idea here is to allow you to see more information without having to unlock your phone. Long press the lock screen, tap the Personalize button that appears at the bottom, then tap Add new (you can’t customize your existing wallpaper).
Change the background: The usual wallpaper options here are a photo, pattern, or solid color. You can also, for some reason, make a collage of up to six emoji for your wallpaper. Swipe right on any of these for additional looks. New dynamic wallpaper options include random photos (choose a person or your own combination of images), showing an approximation of the weather outside, and some space-themed backgrounds like the solar system or the moon. The depth effect setting (three dots in the lower right corner) places the subject of a photo in front of the clock.
Add widgets: Next, you can add some “widgets” – little boxes that display changing information. Tap Add Widgets below the time on your new screen and choose up to four small or two large options for things like the weather, battery levels, or the latest headlines. Customize the date line above the time by tapping it to add information like the moon phase.
Also change your home screen: When you’re done retouching, tap Done in the top right corner. Select Set as wallpaper pair to automatically generate a wallpaper for your home screen (the one that appears behind your apps), or Personalize home screen to choose your own wallpaper. You can’t help but set a new home screen wallpaper.
Do more for different occasions: You can add multiple custom lock screens. If you want them to change based on your focus mode (dark and empty if you’re sleeping, headlines, and weather when you’re at work), tap the Focus button at the bottom of the preview screen.
Source: www.washingtonpost.com