I have a hard time telling the difference, too, but to me, S curves are waves (2), and spirals are curls (3). But the longer you're on CG or modified CG, the more you may see your pattern changing.
Former longhair, now CG, living in N. California where the fog meets the wind
3a/b, fine, normal porosity/elasticity, high density
Conditioner wash and style. That's it!