You can remove the Sign Up button from an event, which allows you to have volunteers see the event but not sign up for it. This is useful if you need to post an event as information only or if you prefer to register users manually for the event yourself.
To post an event without a Sign Up button, simply edit the event and toggle the Allow Users to Self-Register field to "No." In addition, ensure that your event's Event Visibility setting is set to "Show this event when registration is deactivated."
If you need to let volunteers to self-register for the event later, simply edit the event and toggle the Allow Users to Self-Register field to "Yes."