I have a white board in my kitchen where, every Sunday, I organize my week across the following categories: House, Office, Kids, General To Do, and Dinners. I grocery shop on Mondays. Every Sunday I also schedule gym time and plan my workouts.
Don't fret about exercising late at night. It's better to get that workout in than to hold it off for the morning when you'll be too busy and it will be way too easy to say you don't have time.
I find that if I decide the night before how and when I'm going to get my exercise the following day, I'm much more likely to do it. Every evening I decide whether I'll go to a class at the gym or go for a long walk or if it will be a day off. That way, it's already in my head when I wake up!
Working out at the same time each day (whether morning, afternoon or evening) helps make exercise part of your daily routine, and just becomes 'something I do at this time' rather than something you need to get specifically motivated for.