I think the best way to advertise a new event is to give some consolation prizes for the losing teams (at least for the first 3 events or something like that), so that they will be encouraged to join knowing the fact that they'll lose anyway( undergeared, newbie, etc). As a new player, its good to have a taste on how intense the PvP system in this server or how cool this server is, thats like the main motivation for newbies in a PK server out there! :)
Just saying though :)
More powerr!