Have a look at this link as the explanation are very good and there are some do's and don'ts as well as some menu ideas.
lowcarbfreshwell.co.uk
What approach you take is your choice but really it has to be enjoyable and sustainable as it needs to be a new way of eating.
Knowing what carbs are in various foods is important as it allows you to make sensible choices about what to have and what portion size. Looking on packets will become second nature or on the internet for the TOTAL carbohydrate of what ever food it is. You would then have to work it out for the portion you are going to have. So if something says 50g carbohydrate per 100g and you are going to have 50g then it would be 25g carbohydrate. Having some scales on your worktop will help you decide what your portion is.
The book or app Carbs and Cals is very useful as it gives pictorial images of various portions of a whole range of foods and meals.