With no technical knowledge, you shouldn't hire a programmer.

But the way you write about this, it's as if you are assuming you cannot gain technical knowledge. Unless you are a rock, this assumption is probably false.

So first step, learn about the domain of concern. Including some technical knowledge. You'll need at least enough to decide whether your plans are well considered, and to communicate your intent to whoever you might hire.

Then you could learn about hiring: http://lmgtfy.com/?q=should+I+hire+a+programmer