Choosing the Logo for your event site can be done by navigating to Event Website and then Images.
Adding A Logo Image to an Event Site
Click the Add New Image Button.
Browse or drag and drop the image you want to use for your logo.
Change the Name input to be "Event Logo"
For Image Type input select "Logo"
Optional: Enter a Https Link
If provided, when this logo is clicked it will navigate the user to the link that was entered.
Click Add Image to save.
Click on the Event Logo filter at the top of the page and verify that you only have one image that is marked as logo.