Given the large number of daily events, your event will need special advertising in order to stand out. Traditional posters and ad placements can be coupled with all kinds of different promotional measures tailored to the target audience. Advertising options, price categories and other related information can be found here.
The Hamburg Marketing GmbH media server also provides materials for flyers and posters. 

You can also use the Hamburg Tourismus GmbH events database. Once entered, your event will become visible to the media and regional websites, enabling it generate more reach.