A lot of people have a lot of ideas. People have to figure out which idea they want to commit to. You want to eliminate all of the roadblocks and potential reasons for someone saying 'No'. Address them in order of importance.
- Get along!
- They should be someone who complements you. Figure out what your business needs, and you will have a better idea of who your cofounder should be.
- You're more likely to find a co-founder at a conference either on startups/entrepreneurs or at a conference about your market/industry/field