[bitL]

First, try just 1-2 days but remove all caffeine/sugar like a week ahead. Once you can do 1-2 days without any major problems, try doing 3 days (Friday + weekend). Once you are fine with that, try 5-7 days, water + electrolytes only, no food, no juice; drink however as much as you want, if you feel weird, drink more (always with electrolytes). If something really feels off, have some energy bars ready to intervene and break fast quickly and safely. Also, check yourself for diagnoses that might respond badly to fasting and in that case avoid doing it.

[TurkishPoptart]

Thank you for this. Can you comment as to why you think it's necessary to remove all caffeine and sugar in advance? The reason I ask is that I have a penchant for black coffee and imagine that it's useful as an appetite suppressant.

[bitL]

Because you might have nasty withdrawal effects like strong headache on the first evening that could persuade you to break the fast immediately. You can gradually tone down your coffee intake so that at the beginning of the fast you won't have those effects.

[sizzle]

Can you safely fast if you rely on medication?

[bitL]

Discuss this with your physician. People who have e.g. problems with kidneys should not fast.