Select the tab Contacts where all your guests are listed. To edit contacts or complete them with more details you can click directly on the name of a guest and then top right on Edit contact.
In addition to general contact information, such as phone number or email address, you can add notes that concern the guest. E.g. if you know that Mr. Jones prefers a table next to the window or that the Smith family needs a high chair, you can leave a note for your colleagues. So everyone of the team knows what to do and you improve the service.
Related articles: Create contact