Great question!

Many years ago I read someone describe it as "waterfall" -- the sensation of long hair running over your skin. Whether it's Lucy's "hair tickle" or some other technique, a woman's hair in motion across a man's body is the best sensation. Swinging, dragging, whipping -- it's all good.

Number 2 for me is wrapping long hair around my cock and jacking off with it (or being jacked off). Feeling the wrapped hairs sliding over each other, and the skin of my cock, is heaven. It's similar to the sensation you get if you wrap your cock in a couple layers of a silk scarf or nightgown to jerk off. But hair is better.

Number 3 (which I haven't really experienced) would be using my cock to poke around in a big, loose bun or french braid of some sort. It sounds like an adventure, but you never know. If the bun's too tight, there's not a good way to get in.