Exercise
Take in more water , less carbohydrates foods
More basal insulin and less boils insulin. Since the basal insulin stays in your body for 24 hours or 48 hours (depending on which insulin brand you use) it will slowly be reducing your BG after the bolus you injected has finished working...
Check you blood glucose level and how high or low it keeps going will tell you whether you injected more or less. I think for today you should be on the 2 hourly glucose test