When cutting I usually get my RMR tested ($80) then set my caloric level around there (it's been about 2200 the last few times). This makes sure that with some activity and training I'm in a solid deficit daily but not risking slowing my metabolism down. Then I go 2.0g/kg protein, 1.0g/kg healthy fats, and make the rest of the cals up with carbs - sometimes I'll drop lower on the carbs and higher on the protein though if I have a lighter training day and don't "need" the full glycogen stores. Fuel for the work required!