Source: Martina. "Measuring Ketones." Web blog post. KetoDietApp.com. Compumaster Ltd., 30 Nov. 2013. Web. 14 Apr. 2016. <http://ketodietapp.com/Blog/post/2013/11/30/Ketosis-Measuring-Ketones>.
Generally, ketone concentrations are lower in the morning and higher in the evening. Whatever time you pick to measure ketone levels, make sure to keep it consistent. Also, do not measure your ketone levels right after exercise. Ketone levels tend to be lower while your glucose levels higher so you won't get representative numbers.
Keep in mind there are daily fluctuations caused by changes in hormone levels. Don't get discouraged!
Another aspect that affects the level of ketones is the amount of fat in your diet. Some of you may show higher concentration of ketones after a high-fat meal. Coconut oil contains MCTs that will help you boost ketones.
To easily increase your fat intake on a ketogenic diet, try fat bombs - snacks with at least 80% fat content.
Ketone levels tend to be higher after extensive aerobic exercise as your body depletes glycogen stores. Exercise may help you get into ketosis faster.
ketogenic "fruity" breath is not pleasant for most people. To avoid this, drink a lot of water, mint tea and make sure you eat foods rich in electrolytes. Avoid too many chewing gums and mints, as it may put you out of ketosis; there may be hidden carbs affecting your blood sugar.
Increase your electrolyte intake, especially potassium. You are likely going to lose some sodium and potassium when switching to the keto diet.
Finally, if you find it hard to lose weight on a ketogenic diet, there may be plenty other reasons than the level of ketone bodies: Not Losing Weight on Low-Carb Ketogenic Diet? Don’t Give Up and Read Further.