Discord added the ability for Nitro subscribers to add a banner image to their profile. However, users can currently only change their banner image from Discord’s desktop application. This ability isn’t available in the Discord mobile app.
Our guide will show you how to change your profile banner image in the Discord desktop app.
Note: These screenshots were captured in the Discord app on Mac.
Step 1: Click the gear icon to the right of your username in the bottom-left corner of Discord.