I have a great product idea but I dont know how to make it a reality. What can I do?

I have a great Idea but that all it is and idea. how do I plan,work it out, and start being able to market this idea. I ts really great but theres a patent i have to get,stuff i have to develop and i dont know anything about that stuff all I have is the I dea, how can I start to develop it?