Like any task in your company, hiring needs to be a process that you create, maintain, and improve. It also needs to be thorough and reviewed with others who are involved.
Look for some experts in this field to help you. If you’ve never been trained to hire someone, you probably just use the techniques people used on you when you were being hired in the past. Instead, consider implementing a systematic scoring system. This way, the search is data-driven, not just by a gut feeling.
-Aaron Montgomery, 2 Regular Guys, MontCo Consulting