There is not a accurate formula to get used to altitude if you come to Peru, but there are some recommendations for it.
The first one is once you get to Cusco or any other city located at high altitude, is to take it easy. Don´t do much excersise, rest a couple of hours and eat light. Digestion turns slow in the altirude.
Before you come to Peru, check your hemoglobine, your target is 15mg. Once you are at high altitude, this will be the key to a goog acclimatization. Also, previous months for your trip, increase your reserves of Iron in your organism. Iron in your bones will turn into hemoglobine once to get to altitude.