Start with the little ideas. I like the suggestion that you never say, "Your Dad" and you just say "Dad." Not "Your dad will be here to pick you up in a few minutes" but "Dad will be here to pick you up in a few minutes." I found that one to be an easy one to do.
Find a few that you know you can do. Make a pledge to yourself that you will do whatever you need to do FOR THEM. You'll be proud of yourself and know that you are doing what your kids need. I found that in my mind I had to take my H out of the situation because I, too, just couldn't believe what he was going to do to them. Instead of focusing on that, I focus on what I can do for them because the separation was inevitable.
Me: 42/H: 37 T: 10 years/M: 8 D9, S8 Bomb: 7.23.07 Separated: 1.20.08 D Final 3.19.09 Affair started in '05, found out parts in 11/07. They married 11.26.09