There are a few things that you'll need to plan ahead of time. First of all, most cities have a historical society that host "walking tours" of local cemeteries. If your city doesn't offer that, contact a historical home or destination that has a cemetery on site, and make arrangements to rent the space including the cemetery, for the evening.
(Remember you need to go through the proper channels to be at a cemetery after hours, because that would be "trespassing"....and you don't want to do that!) And find out if anyone on site is available to be the cemetery tour guide. Most of the time, they have someone on staff who is quite the historian and knows a lot of information about the cemetery and some of it's more popular inhabitants.
Once the arrangements have been made, this is where you get creative:
- Make sure to mail each of your guests a formal invitation
- Serve a spooky sit-down dinner
- Rent a limo to take your guests to and from the location, after dinner
- Once you return from the cemetery, cocktails are served
- Host the seance.