Intermittent fasting has the effect of regulating your blood sugar and is an option depending on the type and severity of your diabetes.
Otherwise, it's switching to "slow carbs" that are broken down slowly so it doesn't spike your blood sugar. These are all vegetables and some fruit.
White rice, through the polishing process becomes a fast carb and spikes your blood sugar, unfortunately. So reducing white rice intake helps regular blood sugar.
Pasta, due to the processing, also becomes a "fast carb".
Fortunately, new reseach has found that cooling down white rice and pasta converts them into a resistant starch variation. Reheating it doesn't take away this property.
So, cook rice ahead of time. Let it cool down. Then reheat it before eating if you just have to eat rice and pasta.