That is a good plan, but use it alongside some sort of food diary and record your levels next to that meal. This will show you if your meal was suitable or not, then watch for trends. I used to put all parts of the meal down including any sauces/gravies, and counted the grams in the carbs in that meal. You can also test immediately after getting up before any activities, and before bed. Once you start to get the hang of things, you could also test between starting your meal and the 2 hour mark - at an hour or 90 minutes, and after the 2 hour mark to make sure you are on your way down and not up.