I was in your shoes a bit over 2-years ago and still going at it, so, if I may, give you some pointers.
1. Before you leave your full time job, model your expenses for as long as you can (did that for six months) and make sure you have enough to see you through both good and worst case scenarios. This will also tell you where the stop-loss is for you.
2. Have a list of people who you can lean on for emotional and intellectual support. It only takes one bad day to pour cold water on all the good days. Make sure that you have people who will keep you moored on both the good and bad days.
3. The first month is the toughest one and nothing in the world prepares you for it, especially if you have been securely employed for close to a decade.
4. Make sure you are doing what you enjoy doing & aim for revenue that will take you out doing things that you don't enjoy doing at the earliest.
Good luck, again :)