Identify and tackle risk early
Risk is everywhere and it's not possible or a good use of resources to mitigate against it all. Start by identifying different risks and categorise their severity so you can judge whether or not you need to mitigate against them and when you feel the risk is sufficiently high, consider what you're going to do to reduce it to an acceptable level. For instance, if there's a particularly high technical uncertainty in a core part of your proposition, you may choose to do some R&D to prove feasibility. Whatever you do, tackle anything high risk head on: leaving it to later will end in tears.