1. Make sure you share similar values and complementary motivations for starting the business.

2. Identify your respective strengths, weaknesses, and interests.

3. Be open and honest with each other, always -- especially when it's uncomfortable.

4. Get some wins together. Accomplish some key tasks or objectives as a team.

5. Have a defined process for how to make decisions when you don't agree. e.g. certain decisions are handled by one, others require unanimity, others require input from both but the tie breaker is...