If there are a lot of slides and many presenters have several presentations, consider a slide review for all presenters the night before.
Work out all of the kinks and formatting ahead of time for all the presentations.
Don't make the changes 5 minutes before the show or after the show starts (tell your technical team of any last minute updates or complications. They should be available 24/7).
If you have simultabeous translation, definitely insist on a slide review to meet the translators and review the content.
have a meeting agenda
Ask for input before the event.
Give people (presenters, vendors, etc.) time to respond
PROVIDE SNACKS AND LUNCH
If it is an all-day meeting: coffee breaks and snacks/lunch.
If you start early, have welcome coffee.
BE MINDFUL OF TIME
Start the meeting on time.
In opening remarks, remind everyone that delegate's departures may be affected by presentations running late.
Keep the meeting short (as short as possible to get the "message in the meeting" across).
KEEP ON TOPIC
Walk around the room, see what people are engaged in and if you have engaged them.
Consider using Presenter in the Center (sample room set up shown).
Complete the Concept, Topic, and Keyworks in the form of either a Flash Drive, Handouts, or explain where online you might have the general information seen today.