You can easily become ketotic (get into ketosis) by fasting in all of its forms (intermittent (12-18 hr) to Extended (3 - 10+ days). Jason Fung’s new book has recent (Oct 2016) medical discussions of the different types of fasting and a section on How to Fast.
Simple is good, Stop Eating is the simplest way to get into ketosis…
And constantly Study what you are doing to maintain your most precious possession, your health!