A running event coordinator will plan your race event professionally. The person has training and expertise to handle this task. You should start preparing for this event at least a year in advance. Allow participants and other people plenty of time to prepare. Be realistic about the number of people who will join the race in the first year. As the popularity of event grows, more and more people will join it in the coming years. Organizing such a large and moving event requires support of professionals specializing in this field. A wide range of tasks are associated with it.
You not only have to manage the event activities but also its marketing and management. Lots of staff and even volunteers are needed to make this event a great success. As your event grows every year, you will need more staff to manage it. Keep improving and note down the problems you faced in managing earlier events. Those problems should not be repeated and solved early before they affect the event happenings.