The better you know each person the more ‘degrees’ you will be able to take that person's relationships out. If you can link up on LinkedIn (a system that tracks the degrees of separations in relationships), do so. Think through who you know at the gym, at church, the grocery store, your wine club or poker guys, golf buddies, etc. There are literally dozens, if not hundreds, of people that you know and the second and third degree relationships can number into the thousands. Capture them in a list and start to map out who you know, who knows whom and who knows what.
Once you have this list compiled, study it for the relationships that may lead to important introductions, the relationships that you want to learn more about and the resources your network has available for you to leverage. What you will find is a list of contacts that represent a rich environment for networking and connecting people together. This is the essence of rainmaking.