If you're like most entrepreneurs with a great technology idea, you'll be tempted to skip all the planning and validation stuff and jump straight into building your product.
RESIST THE URGE.
Building a simple, easy-to-update prototype and sharing it with as many people as you can BEFORE building your initial product will help you ensure that you are building something PEOPLE ACTUALLY WANT! You might think your idea is the best thing since sliced bread, but what if your view of the world is skewed? What if you're 1 degree off the mark? Or 50 degrees off the mark? How do you fix that if you've gone straight to the final product?
Prototype it, simply and quickly. And LISTEN to your interviewees.
(What is it about sliced bread that makes us compare everything new to it?)