Mkid's Most Excellent® Tips and Tricks on Going to a Large Convention
1. Withdraw cash beforehand
There is nothing more frustrating than going to a convention and not knowing where your local bank branch is. Withdraw as much as you'd want to spend the day before leaving so you'll have one less thing to worry about.
2. Google Street View the area around the convention if you're from out of town.
Let's be honest here- con food is expensive as shit. If you use Street View around the convention area, you'll be able to find either stores to pick up snacks for cheaper or quick fast food restaurants. Warning about the fast food: especially if it's a 24 hour chain, the closer to the convention it is, the more packed it will be.
3. Room keys should be given to the most responsible and most likely to be part of a larger group.
I especially had a bad experience with this last year, where one of my roommates ran off with the key I had and had no way of getting a hold of him as he went off and did his own thing. Amongst other problems he caused, he's not going to be rooming with our group this year.
It may vary by hotel, but usually you'd get two keys per room max. As long as you give the keys to responsible people that would be easy to get a hold of (if they don't own a cell phone, make sure they're grouped with someone who does), everything should go smoothly.
I'll be adding on more as I think of them.