Answer:
You can encourage feedback & send Thank you's since everyone likes to be appreciated. Also a good thing to do is engage in social media. Make sure to also be balancing the budget. Update the website every once in a while. Some other things you can do is extend the duration of your event. Also, try taking the time to be critical of yourself & your team. You need to deal with your event in details to see what worked well and what worked a little less. By doing this you will more easily be able to highlight possible margins for progress for future events. Also try to not to forget to pay any bills.