Include the phone number of a person who can provide more detailed information. Put at an interesting headline at the top, have lots of white space on the page to make it easy to read, embargo the story so it can not be published before the nominated date. Fax the pages off to journalists who cover this sort of story, a couple of weeks in advance so they can include it in their timetables. You will need to follow the media to identify the appropriate journalists - they could be the science, technology, environment, medical, aviation or financial correspondents, depending on the subject of the conference. Follow up the fax with a phone call.
Journalists are often frantically busy.
In the process the conference organisers gain an insight into what the media thinks are the best stories. They need to be at the phone numbers you gave to the media, at the times you said they would be available. Think of equipping them with a pager or a mobile phone, so you can locate them easily during the Conference. Media needs pictures, but conferences are visually dull. See if you can organise interviews in an interesting location nearby, such as a laboratory or a research site.