Make it easy on yourself.
Just make sure to have a protein with every meal.
Eat your carbs around your training or in the morning/afternoon when you are active and will be able to use them.
Post workout after lifting: ratio of carbs to protein 2:1, chocolate milk , cereal, rice pudding are some good examples;
Post workout after cardio: eating a regular meal within one hour is fine. Protien, veggies and good carbs.
Always eat something prior to lifting weights: apple & protein shake , tuna, etc.. you need energy to lift well.
Same for cardio.. I do fasted cardio in the morning because I actually wanted to burn a bit of muscle and decrease my size a bit.I am short. There is some debate on fasted cardio and is not for everyone.
Keep healthy snacks in your purse like nuts, protein powder in a plastic baggy, peanut butter, apples so that when you are hungry you can eat something else and don't go for fast food.
Stay away from diet sodas and fruit juices. Make your own to take with you.
---If I can think of anything else i'll post it