Steve Blank and Eric Ries have great books on the subject. But if you want a step-by-step process, I'd read Ash Maurya's Running Lean. We pretty much followed i

Steve Blank and Eric Ries have great books on the subject. But if you want a step-by-step process, I'd read Ash Maurya's Running Lean. We pretty much followed it to a T and ended up with a validated solution that now has hundreds of paying customers.