To create an event you have to create a service item (service item = event), which will include all the details about your event, except for date and time - that will be done in the next step.
Fill in the name of your event and add description. You don't have to fill the Short description, only the Description. Choose the category and click on Plan type: Units.
Go to next step to add images.
Main service image: Use the best photo that describes your event.
Other service image: another high quality pictures.
Image should be in 16:9 ratio.
Last step will be to set up the date and time of your event.