The first step in systems advocacy is to find others who are experiencing the same problem that you are. The group does not have to be large - at least at this point. A small core group can involve others to support its position later. The most important considerations are that the members of the group agree on the nature of the problem and are committed to a long-term effort to change the situation. Finding interested group members is not hard.
People often enjoy working as a team toward common goal.
The tough problem is keeping people involved over a long period of time. Keeping members involved requires that all feel a sense of purpose. To create this sense of purpose, there must be clear and specific goals that are achievable in a reasonable amount of time and whose achievement will affect people's lives. If there are many goals, they should be prioritized and worked on one at a time. Otherwise, members will lose their sense of purpose.