You can invite people to an event once it has been created. Simply view the event in the Admin area and click the ‘Invite Guests’ button.
From here, you can add selected individuals, groups, or people views to your pending invites list. When you’ve selected your guests you can then choose to send their invite instantly. Once you’re ready, click the ‘Add to Guest List’ button to add your guests.
You can also opt to email invited guests at a later time by clicking the ‘Contact Guests’ button in the event sidebar, when viewing the event in the Admin Area.