I've been reading Jenny Ruhl's book, Blood Sugar 101. If you would like to learn more about type 2 diabetes and the low carb high fat moderate protein diet (LCHF diet), her book will give you
a lot of helpful information. In the UK, Trudi Deakin's book Eat Fat: Step-by-Step Guide to Low Carb Living provides an excellent overview of how to do the diet...
http://www.xperthealth.org.uk/at-risk-of-diabetes/a-step-by-step-guide-to-low-carb-living
It's an individual decision. My highest blood sugar was 282 mg/dL (15.7 mmol/L) when I started the LCHF diet. I used Richard Bernstein's recommendation of 6 carbs for breakfast and snacks and 12 carbs for lunch and dinner. I eat three meals and two snacks a day, so my total daily carb count is 42 (6 + 12 + 6 + 12 + 6).
My diabetes is more advanced so it's taking a long time to get my BG readings into the normal range. For most people, I've read it takes a week, 2 weeks, perhaps as long as a month.
This is week 8 for me. My first week, 0% of my blood glucose (BG) readings were under 140 mg/dL (7.8 mmol/L). This past week, 75% of my BG readings were under 140 mg/dL (7.8 mmol/L), so while I've made a tremendous amount of progress, I still have a ways to go before 100% of my BG reading are under 140 mg/dL (7.8 mmol/L). I may have to take a medication to get my BG into the normal range, but I'm going to give it another 2 months.
Jenny Ruhl has a calculator that might be helpful to you...
http://www.phlaunt.com/lowcarb/DietMakeupCalc.php
Hope that helps.