As others have said, on twice daily injections snacks really are better. I was on 2-a-day when I was first diagnosed, & needed a mid-morning snack, mid-afternoon snack and small supper on top of 3 meals. However, this was nearly 18 years ago!
My parents found what worked best was routine. Up at much the same time every day, meals & snacks at much the same time, & carbs for each meal & snack much the same from day-to-day (e.g. around 30g of carbs for brekkie & around 15g for mid-morning snack, etc.).
However, I must stress that this is only my experience from a very long time ago. Advice may have changed by now.