The diabetes logbook: You can't manage what you can't measure
The other day, I was talking with a friend who has type 2 diabetes. We are about the same age and were diagnosed at roughly the same time. He is on metformin and takes it daily, but relies on his quarterly A1c test to tell him how well he is controlling his blood sugar. He doesn't test himself. He told me that his A1c is 7.1, which is a bit on the high side. I guess it works for him, but personally I prefer to test myself more frequently. On the suggestion of my physician, I normally test about 3 times a week, unless there is something going on, like illness or medication that can raise my blood sugar. Then I test daily.
Recording all activities, not just blood sugars
I have the most success with managing my blood sugar levels when I keep a log of activities. I record what I eat at each meal or snack and the carbohydrate count. I weigh myself daily and log that number. I make an entry for exercise, noting time spent and the activity. I use a computer spreadsheet in Excel, but a handwritten diary would probably work as well. When I get out of the habit of keeping my log, I have a tendency to gain weight and slack off on the exercise.
By keeping my log religiously for the first year after I was diagnosed, I was able to lose 40 pounds, get my blood sugar down to acceptable levels, and learn how to estimate carb counts for my meals and snacks. The bottom line is that I need that discipline to keep myself on track, because you can't manage what you can't measure.