Make time for introspection. You will find a need to take a deep look inside and be ready for this new challenge. Get a grip on your feelings. Writing them down in a journal or in a password-protected computer file can really be a good way of looking objectively. Consider your strengths and weaknesses and find ways to compensate for the things you have a hard time with. Get comfortable with yourself and it will go a long way to your healing efforts for yourself and your family.
Focus on health. Some dads deal with the stress of this situation by holing up or binge eating. Make sure you don't go there. Make time for exercise, even if you have to do it with one or more of the kids. Walk, run, hit the gymjust stay active. And make sure that you eat right. Resist the temptation to subsist on junk food. Keep lots of vegetables in your life.
Consider early mornings. Once the kids are up and around, its harder to make time for you. And at night, there are lots of temptations like TV and the computer to distract you. Get up an hour earlier than the kids and make time for exercise, reading, getting organized and maybe even some meditation. Investing one early morning hour in yourself can make a marked difference.