For events that are regularly viewed for information or related to certain major events at the club, it can be effective to put a cover image on the card.
Find the event, click on the three dots in the upper right corner and then you can select the photo you want to use. After that you need to click on save.
This is done easily on the web by going to the event and selecting "Add cover photo". After that you choose the file you want an then click on upload picture