You've not started learning this step.
Meet more than 30 developers. Each developers had better be engaged in different areas. Each developer may have different experience, skills and working habits. If you meet more than 30 developers, you'll be able to meet and find out suitable developers later. You can be familiar with developer's culture also.
You don't have to have your own business item now. It's even better to meet developers without business item. (You may find the item during meeting many smart people.)
Men or women with their own business item usually have a strong sense of purpose. They have great passion to take tough challenges such as doing start-up. But sometimes their passion make them impatient and stubborn. These kind of stubbornness may make other people (especially developers) little bit uncomfortable.
You already have your own business item? It'll be changed very much. You think you and your item is too great to be changed? Oh, hell, no!! Be confident but don't be childish!
Find developers networks and communities. If you are student, visit programming circles. There are many online communities also. for example,
Python Developers Group https://www.facebook.com/groups/2249498416/