Question: how do i calculate how much insulin to take?
Answer: Basal/background Insulin Dose. = 40-50% of Total Daily Insulin Dose. ... 
500 ÷ Total Daily Insulin Dose. = 1 unit insulin covers so many grams of carbohydrate. ... 
Correction Factor = 1800 ÷Total Daily Insulin Dose = 1 unit of insulin will reduce the blood sugar so many mg/dl.