I would look for a person who is comptetent enough to make you a plan and you trust him, i.e. how to properly enter fasting, how to act during fasting and how to return to a regular routine.

Another alternative, is stick with intermediate fasting everyday, where you finish eating at 6-7pm and start 9-10am next morning. Of course, start you day with water and hydrate enough during a day so you don't want to snack too often.

When I do a cleaning or fasting I do them regularly, few times a year and try to align with solstices and equinoxes. One of the practice I like is Shanka Prakshalana