The event background image is displayed on the registration page of your event and can be changed anytime before or during the event.
We recommend uploading an image of 1500x600 pixels to get the best results. If you don’t upload an image, the default photo will be used. Also, note that whatever image is uploaded cannot be deleted; can only be changed.
To add/change the image, go to your Event Dashboard > Setup > Theme.
Under the event banner section, choose a file or drag the file into the box to upload it. Don't forget to hit Save!