Open the YouTube app or go to YouTube Studio
Sign in to your account
Tap the Create button or Upload button
Select the short video from your device
Make sure the video is vertical and 60 seconds or less
Add a title
Add a description if needed
Choose a thumbnail if available
Set the audience for the video
Select visibility options such as Public, Unlisted, or Private
Tap Upload or Next
Add any final details
Publish the video