Ask HN: What follows after a great idea?

Ok, so, there is a lot of talk about startups and new businesses. However, despite the number of sources I read, I can't figure out where to now. I have several great ideas for products, small-batch start up. Eventually an UNfinished plan for expansion and so on, but I am just sitting around with these ideas in my head and don't know what/where to continue.

Do you register the company first? But how do you register, if you have no personal capital, and would depend on VC funding. Do you look for partners/co-founders first? . . .

Where does one go after the birth of a great idea? Is there a step-by-step guide for making your own business?