How do you catch your first customers?

My preferred approach is to hang out where they hang out. Make 'friends', connections, get known. Along the way share things you are working on in a non salesy way.

Also, the 19 channels of traction are a useful point of reference to think about the options you do have.

Research where your potential customers read their news, and try and in get contact with a columnist/blogger who writes about things that your potential customer care about.