1) (Goals can be hard to keep. A recent study shows that a whopping 92% of people fail to meet their goals. With a mastermind or personal board of directors, you can set goals and have your co-members help you stick to them).
Make it goal-oriented.  I have a specific structure for setting goals (watch my goal-setting training on it here) and your mastermind group should have one too. Everyone can have their own goals — but there needs to be some goal so that your group can have accountability. A mastermind group without a goal is simply a hangout.
Once you decide to meet twice monthly, make sure you meet bi- monthly. The moment you lose consistency, you lose accountability.
Here are some of the top reasons to consider starting or joining one:
Related Industries or Same Job, Different Industry. The perfect mastermind group is made up of people who are in related industries (so everyone has the same lingo but aren’t competitive) or are in the same role, but in different industries.
We have the same business models, but no competitive audiences.
I know mastermind groups or Personal Board of Director Groups who meet every week, I know others who check-in once every six months. Have an idea of how often you want to meet and tell invitees what to expect. The goal with timing a mastermind is accountability and progress. You want everyone to have enough time to get their homework done BUT also not meet too far apart where people don’t have enough accountability.
3. Define Ground Rules
The best questions to ask in a mastermind group:

What was your biggest success since the last time we met? This gives everyone an opportunity to share a success and get support. We very rarely get as much encouragement as we like — this is a great way to start a meeting (and pushes you to achieve a success to brag about!)
What is your biggest challenge right now? It is good to dig into at least one specific challenge every meeting. Just meeting and chatting is not a real mastermind.

What one goal do you want to achieve before our next meeting? I like to keep goals as specific and achievable as possible. If you want to do big goals like annual or seasonal you can do them in addition to these mini-goals. This also gives people ‘homework’ in between meetings.

How can we help you? This is how the mastermind group can get accountability. Remember: Think of these mastermind group members as your personal board of directors – they are there to help you!