At some point your registration will start (more info about configuring your Registration). From now on participants will be able to sign up for your event over the event website.
A participant that has registered to your event will be automatically activated. This means that the participant is visible to others and can send and receive meeting requests. However, Organisers can decide to manually activate participants after registration. This means that a participant will not be visible as long as he is not activated by the organiser.