Go to the profile page first by clicking “Customize” -> “Profile” and scroll down.
This guide shows you how to change your avatar, music, and other assets.
Click the Options button to open the options. You can change the shape of your avatar, make your avatar use your Discord avatar, and use custom Discord decorations, or match your account’s decoration.
To upload/change an asset, simply click the Upload button and upload your desired asset. Bare in mind, the asset’s size must comply with the limit provided.