Know how your basal rates work. Are there risky periods in the middle of the night or early morning that may cause you trouble? Basal test so you can add confidence. You should know that without eating your BGs won't fall or rise too high. Then I would do some isolated tests with your favorite drinks to see how you behave hourly, for maybe 12 hours. Test with a couple drinks, then 4, then 6. Read this for some illustrations:
http://www.mendosa.com/DiabetesAndDiet.pdf