The Place - Select a place that will be comfortable for your group. To do this take into consideration both your potential audience and the subject matter of the book. More creative or innovative subjects might benefit from more open and informal settings. Also, pick an area with enough room for the number of people you expect, but not more. It's better to have a full room than a mostly empty one. And then when you book a bigger room for your next meeting, it is likely to be seen as a success to others.
Marketing - Do whatever you can to get the word out about your upcoming book club. Do it early and often. It's easy to assume that everyone will know about it after you tell them once. But we are all bombarded with information every day, and it's easy for your book club to slip by. Communicate more than you think you have too and you'll ensure that you get a healthy turnout.
Conversations - The goal of your book club should be to facilitate conversations between people rather than passing on the information in the book. There are a lot of ways to get information out to others - videos, infographics, words on a page - the real gold mine of a book club is the interactions and sharing that can only happen by bringing people together. In this respect, quality trumps quantity. Too many talkers will make it hard for the participants to get value from the meetings and will make it harder for quiet people to feel comfortable contributing. A good rule of thumb would be 5-10 active participants in your meetings.
Keep Track - Have a sign in sheet at every meeting to keep track of who is interested in the topic you're discussing. I learned this the hard way. Face it, you won't remember everyone and if you have a list it makes it easy to cancel or reschedule meetings without having to 'hope' that everyone heard about it. This will also make the next tip easier as well.
Remind & Follow-up - Use your list to remind others of upcoming meetings, what pages they have to have read, and even provide agendas or handouts ahead of time. People are busy and forget, your email to them might be the difference between them showing up or missing out. Following up is also valuable. Summarize the meeting for the benefit of those that couldn't attend. Also, give people an opportunity to ask your questions they didn't want to bring up during the discussions. Good follow-up communication can keep the momentum of your book club moving in between meetings.
What's the Point? - When you're picking out a book and deciding how you want to structure your meetings, always keep in mind what your end goal is. What actions do you want your book club participants to take? Once you have that clearly defined, use all of the above to design an experience that will make taking those desired actions as easy as possible for your audience.
Hopefully I've sparked your interest in having a book club yourself. Are you ready to start?