1. Get everyone involved early
I can't tell you how often I see people overlook getting the entire team, or at least as many people who fall under the responsible category as possible involved in the process early and often. If you can, get everyone in the room during the ideation stage. If not the ideation stage, make sure they're in the creative stage. I love the old adage, "If they plan the fight, they won't fight the plan." So you wanna get them involved.
2. Use data
Use data. I like to use data at different stages of the process. You can use data and measurement as an energizing tool, as your energizing bunny. The best way to feed this bunny is with carrots. But, you might also use the stick. What I meant to say is you can use a dashboard to show people how many RSVPs somebody is driving and get them really excited, or you can show them where you're not hitting, what's not working for you as a way to get people onboard and focused on their goal. I do find that using data at every single stage helps you sprint this marathon that is an event.
3. Communicate a lot
Last but not least, you want to communicate. Communicate a lot. I always would say to my event planning team, "Our entire job, not just part of our job, our entire job is communication, both with our attendees externally and with our team internally." Setting up a communication cadence early in the process, makes this whole machine work.