Why does he want you on the ketogenic diet?  Your ketosticks should just be positive. I would take it several times of day to make sure you stay in ketosis.

The most accurate way to measure your state of ketosis is with a blood test, which is a bit pricey. Urinalysis of ketone bodies is generally most accurate as you are initially transitioning into ketosis, because after about a month or so of eating a ketogenic diet your body often becomes “keto-adapted” and usually will not excrete as many “excess” ketone bodies, which are what is measured in urine. I have worked with many folks on a strict ketogenic diet who never get above a “trace” level of ketosis when measuring their urine because they have metabolically become adapted to ketosis.

Another way to measure your level of ketosis is with a breath tests. Some people find this, or the blood test, to be a much more accurate way of measuring ketosis. But even without tools to measure, if you are eating very low carbohydrate (20-50 g/day) you are probably in ketosis.

I like to measure ketosis with urine ketosticks.  They are inexpensive and can accurately tell you if you are in ketosis.  The reason for this diet is that it can help with seizures and some doctors think some neurodegenerative disorders.  The Atkins Diet (ketogenic diet) helps many people lose weight, but I like our program better because it generally has more nutrients.