There are a couple different ways that you can go about putting a YouTube video in the corner of your iPhone screen. The first way is to use the built-in Safari browser on your iPhone. Go to the YouTube website and find the video that you want to watch. Once the video starts playing, press the "Share" button at the bottom of the screen. From the Share menu, select "Add to Home Screen." This will add a shortcut to the video on your home screen. To watch the video, simply tap on the shortcut and it will start playing in a separate window.The second way to put a YouTube video in the corner of your iPhone screen is by using a third-party app like MyVideoCorner. With this app, you can browse for videos from within the app and then add them to your home screen as shortcuts. MyVideoCorner also has support for AirPlay, so you can easily stream videos from your iPhone to an Apple TV or other compatible device.