Think about it, if you're planning to start a business, you're going to be pouring your life, heart and soul into it. You'll miss out on a social life, you may be eating dry wall and ramen noodles for a year at least. You'll go through some of the most dramatic highs and lows you've ever experienced and through all of this, you need to keep your focus, keep your passion wholly geared towards the success of this goal.
You have to not just like what you do, not just love what you do, but feel an absolutely imperative need to see it through, an obsession with seeing it succeed, of reaching that point of achievement (and then setting a new goal to allow it to grow and fuel your further obsession).
Entrepreneurship isn't just something you do on a whim, it takes guts, it takes moxy, it takes everything you have not to give in.
Get obsessed with your idea. Get obsessed and make it happen.