(last updated: 12/28/17)The following is a quick set of tips on running successful events.
DON'T GET COCKY
It's easy for an organizer to become overambitious, and a missed deadline only communicates to your players that you're not reliable. Underpromise and overdeliver. Give yourself a reasonable amount of time to get all of your material prepared.
SCHEDULE SCHEDULE SCHEDULE
The difference between a conductor and a mess is a watch. Overall, keep things moving. Keep deadlines handy, and make sure your players know them. Not all players have the same sense of urgency, so fuzzy scheduling is a fast way to kill potentially good scenes!
BE AWARE OF TIME
The event itself is about the RP, and nobody's going to be able to start a scene at 10pm on a Thursday. Make sure your players have the information they need to get a scene scheduled in a timely manner--that means that typically you want to make sure your posts go sometime before Thursday, so that Friday, Saturday, and Sunday are open for your players to actually have fun on their scenes. The weekends are extremely critical for scening, so keep any heavy lifting and waiting out of that time period.
THE FIRST CASUALTY OF WAR..
It's tempting to write a plot that's rigidly timed and plotted out to the millisecond, but such plots are typically not practical, often feeling forced and making players unhappy. A good event is a symbiosis between a greater machination and the people's participation. Allow players to guide your plot, and attempt to build narratives around players who really engage themselves in your scheme.
THE SHOW MUST GO ON
Don't get tied up in minutiae. Sometimes a scene just isn't going to finish, no matter how hard you wanted it to. Maybe a player just didn't show up one day, or maybe a set of folks in the third match of round four are having trouble finding a time where they're all available. No matter how important any single scene is, it doesn't trump the needs of the entire plot, and no matter how important any single player might be, they don't trump the needs of that scene to serve that plot. Make substitutions if you must, and write around if you have to, but don't let a single failed scene ruin things for all the other players in your event.