The best advice I can give is be smart. A place near me was called "Wired Warfare" which did OK, but due to financial troubles, sold to Area 51, which is going under right after perchase. This is because they abanonded their core audience and basically changed everything. Best tips.....
1)Know your audience: Area 51 flopped by removing computer, and overcharging for products. The place was hoping even late at night, but as Area 51, no one comes in.
2)Have producst: Another weakness was no items like Bawls or Monsters. Energy drinks that sell well with gamers. This can make up profit loses in other areas, and will sell well with all types of gamers. You should proboly sell soda and candy of some kind
3)Keep it focuses: Another weakness was switching computers oyut for 360s. Was it a terrible idea. Not so much, but they over did it. If you have a console, it might be nice, but it's not going to be what attracts customers. The PC idea worked because LANing is hard and clumbersome. Table top games can be harder since they need a good deal of space. If you get any console, get a Wii. This is the only one that will attract people specifically. A little more on this
4)Advertise: It doesn't have to be much. Just flyers around town and such. That should help. I mention the Wii since people seem to love playi9ng it. Bars even have Wii Sports tournamnts, so it might have people come in.
Twester gave the best advise, so do well to listen to him.