The last part of your event takes place afterwards. Within a week or so of your event, meet with your planning committee one last time. Brainstorm, debrief, and get everyone's thoughts on how things went. What went well? What was a complete failure? If possible, ask guests for feedback as well, and find out what they enjoyed the most, and what they would like to see done differently as well. Use the email addresses you collected at your sign-in table, and send out a short questionnaire to find out what people have to say - and also to recruit potential volunteers for your next event!
If anyone has donated items or money, send them a thank-you note for their contribution. Likewise, if you've had artists, musicians or guest speakers, be sure to write them and let them know how much you appreciate their time.
A Few Miscellaneous Tips:
Consider whether your event should be a family one or adults only. If you're going to allow children, it's crucial that you provide something for them to do. Put one or two people -- parents, preferably -- in charge of a Kids' Zone, and include crafts, coloring pages, and games to play throughout the day. Be sure to read Why Are Kids Sometimes Unwelcome at Pagan Events?
Occasionally, people from outside the Pagan community will show up at Pagan events to cause trouble. If you think this might happen to you, it's not a bad idea to have some measure of security in place. You may want to ask your local police department to stop by and have a presence, or if you know some big, intimidating guys, you can have them stand at the entrance and keep people out who are uninvited. Don't be afraid to eject someone from an event if they've made it clear they're only there to cause trouble.
Try to be inclusive. Remember that the Pagan community consists of more than just NeoWiccans. A variety of groups -- Wiccans, Druids, Heathens, and Satanists -- may show up at your event. Don't alienate any of them by being disrespectful of their beliefs -- especially of one of the themes of your event is Pagan unity.