vfs stand for variable factors rule no. 1 when creating an orbital you need (2vfs)+1 types of that orbital rule no. 2 an orbital that has some orientations, the number on electrons can be on it doubles (there can be 6 electrons on p because px py and pz) rule no. 3 youll need 2^vf sheres/lobes
if these rules are bossy please remember this is based on real science and physics