The Premium Events calendar has the option to assign a Featured Image to the event. This will allow the calendar to display that image in a variety of ways in relation to your event. This is a great way to call attention to special events and dates.
Creating the Best Featured Images
If you want to create the best featured image, here is what we would suggest. Make it rectangular (wide) and keep the main focus of the image in the center. This will keep the idea of the image in tact when it is cropped to a square and also not allow the image to take up too much space when it is on the individual event detail page.