Facebook makes it very easy to organize events and invite friends, colleagues and associates to them. However, it's all for nought if you don't make effective use of the features offered to you as well as bear in mind a few courtesies regardless of how you invite people to your activity.
Here are a few things to remember:
1) Location, location, location!
Coffee shops are very popular to hold informal get togethers and networking opportunities. Be sure to call ahead and make sure they don't already have an event scheduled that might present a conflict. And also make sure when preparing your announcement to specify where in the venue you're going to be meeting. If your location has two floors, specify whether you'll be upstairs or down stairs. If they have a patio, specify if you'll be inside or outside. This is especially helpful for making sure that people new to your networking circle can find you.
2) Know when from the get go!
Don't create an event without a set start time. Trying to get a consensus on a good time from your potential guest list is pointless. Just give people a window of a few hours. They will come when they can, or not at all.
3) Respect your hosts.
You should always encourage participants in your event to purchase something from the venue while they're there. A cup of coffee, hot chocolate—even a relatively overpriced soda—as a courtesy for using their space and often their free wi-fi. Not hungry or thirsty? At least drop a dollar in the tip jar on your way out. The owners and employees are working hard and space taken up by non-paying customers is costing them money. Make your event worth their while and they'll be happy to have you back.