And now it's time to resume our semi-irregular, possibly unending series on starting your own convention. In part three of this series I talked about choosing a location, which is a fairly important step. While you're researching potential locations though, there is something you need to simultaneously keep in mind while planning your first convention: What the heck weekend are you going to put it on?
There are two factors that will dominate this decision -
1. When is the best date in contrast with other cons?
2. When is your desired location available?
Choosing a date is hard for a first year con, because it means in some ways attempting to forecast the future. You are trying to predict the best weekend for an event in a hypothetical future con scene, where some cons might not still exist and others may pop up where they weren't. There's also the dreaded "weekend move" where an established con decides to shift their date by a month.
When I say forecasting the future, I very much mean it too. Whenever I've been asked, I've always recommended that you give yourself not one but two years to plan your first convention. You need time to build your organization and get the word out that an established convention doesn't need. This also may make it easier to get the weekend you want with your preferred venue (if your preferred venue won't let you reserve more than a year in advance, there's a way to deal with that... and I'll talk about that in a bit).
Finding out when other conventions are is fairly simple. There are sites like AnimeCons.com and Containment (who I am in no way plugging because they show UnCONventional on their front page, really) which can help you find cons in your region. Attending other cons will also expose you to fliers for conventions you may not easily locate online. While almost every convention has a website, not every convention has an easily findable website (especially Scifi cons for some reason).
You should look at what weekends any con in a connecting state are on. Don't look at too large of a region (as in, if you're in Illinois, you can't be concerned about a convention in Florida too much), but the connecting metro areas have quite an effect. For No Brand Con we looked for any cons in Wisconsin, but also Minnesota, Illinois and Iowa. You want to be spaced away from these events on the calendar so it isn't a burden for your attendees to try to fit your new event in to their schedule.
Most regions have a "convention season," but believe it or not, you want to be as far away from this as possible. When all of the conventions in a geographical area happen around the same time of year, it means everyone has less money to spread between them. No Brand Con is in the spring, and while there are a bunch of cons in this area during that time of year now, there were only a few in the region when we started. Now the con season has reached saturation, and we spend our time worrying how many weeks between Detour (the larger con in the region) and us there are.
Most conventions are between February and April in Wisconsin, which is why when Geek.kon and Daisho Con both established themselves in the fall (Geek.kon in September and Daisho Con in November), they were able to build and sustain a larger growth than if they had set their dates in May.
Ideally what you want to do is find the gap in the calendar so large that there is at least a month between you and any other convention. Frankly, if you can't, then you may be in a region where there are too many conventions already and you may just want to scrap this endeavor.
The other issue which will effect your date is when your desired location, be it a hotel, university center, or back of a bus terminal, is available for reservation. You are competing against weddings, university functions... and I guess bus schedules for that last one... so finding an available date can be a challenge. By planning your first event two years in advance, you will mitigate some of these problems as most groups won't try to reserve that early.
If you can't reserve your convention date that far in advance, then you still want to target a time period. Early fliers for No Brand Con 2002 merely said "Spring 2002" for their date as the University center we used to use wouldn't let us reserve the weekend as far in advance as we were planning. I cannot stress this enough, so I'm going to bold it and put it in all caps: NEVER PUBLISH A DATE UNLESS YOU HAVE IT CONFIRMED WITH YOUR VENUE.
For a first year convention it is vital that ink be on the contract, and everything locked down. While an established con might be able to reserve their weekend on a handshake (depending on the venue), a new con is an unproven commodity.
Getting your date locked down is going to be your largest challenge, and finding the right timing is going to be hard. I cannot stress the importance of research (and looking at historical dates -- just because Convention A is in March this year doesn't mean it's not normally in April) and finding out as much information as possible. And, as previously stated, NEVER PUBLISH A DATE UNLESS YOU HAVE IT CONFIRMED WITH YOUR VENUE.
I'll disagree with you on the month buffer. NBC may have been in a relatively open calendar for anime cons, but the spring calendar was pretty loaded with cons of other genres. We ended up competing over vendors and even dealt with a minor turf war in the Madison area due to proximity of dates, if you'll recall.