Hi! Teting at the same time of day isn't the key. Testing two hours after eating is the key. At that stage, it should be below 8.5,(NHS target) or ideally even lower (below 7.8). If it isn't, you need to cut out some of the carbs you had in that meal the next time. It's not just about sugar and cake; all sorts of things have carbs. Fruit, some veg, (particularly potatos and parsnips), rice pasta and so on. So look at the nutrition guides on the side of the packets, or if it's loose food google " carb content of" to look it up.
You'll get there, and well done on the progress so far.