To determine if your diabetes is well-managed, monitor your blood sugar levels regularly and keep them within your target range. You should also have regular check-ups with your GP to assess your overall health, including your HbA1c levels, which give an average blood sugar level over the past two to three months. Additionally, pay attention to how you feel physically and emotionally. If you're experiencing fewer symptoms related to high or low blood sugar, and you're maintaining a healthy weight and lifestyle, these are good signs that your diabetes is under control. Regular communication with your healthcare team can also help tailor your management plan effectively.