Do you mean painting the transmap?

If you do, I don't know of any tuts, I have done it for myself, just using various different hair brushes, there are lots in the marketplace. It is basically just a case of painting white hairs on a black background, following the UV map. I found the brushes in these sets very helpful -

Antjes Hair Brushes
Hair Texturing Kit

The best & most beautiful things in the world cannot be seen nor touched... but felt in the heart.

Helen Keller

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