If it were me; I would test once per month, two hours after a high carb meal.
If you can meet these, you are doing GREAT:
Fasting BG 70-99 mg/dl (~3.89 mmol/L - ~5.50 mmol/L)
BG 2 Hours After High Carbs < 140 mg/dl (less than ~7.78 mmol/L)
Reference
Conversion