petite-madame:

Hi anon ^^

Thanks a lot for your question and for enjoying my art so much ^^

May I ask, how you draw hair to be so detailed? 

It depends what kind of artwork you are talking about. When I draw realistic style (without a black line art, that is to say like in this art), here is how I do it:

1. I define the palette. I try to use a palette as subtle and
   natural as possible so that the hair looks natural, precisely. In other
   words I very rarely go for a super bright yellow for blond hair.
   NATURAL.
2. With the darker colors, I block the colors. By
   “blocking the colors”, I mean blocking the shape of the hair because
   hair is a shape. It’s important to draw the general shape of the hair,
   whatever the haircut, before taking care of individual hair. The worst
   you can do is starting to draw hair strand by strand, on a white
   background. Horrible.
3. Then with medium size brush, I draw
   the first strands, using medium tones. The idea is to give the general
   texture of the hair, the strands, the curls, etc. If you try to draw
   hair one by one it’s gonna look ridiculous, like in these video games of
   the 1990′s where you could see every hair individually (and no, it
   wasn’t a good thing. It looked fake as hell)
4. Then, with a
   small size brush I draw the lighter colors and I refine the details.
   This is where I draw the tiniest strands but not on the whole hair. Here
   again, I only draw them at specific places: on the forehead, above the
   general shape of the head (where the light hits), near the ears.
5. Finally,
   I add with a round edge brush some shadows on specific places: near the
   roots of the hair, the ears. That’s what is important with hair:
   knowing where to place shadows and highlights (along with simplifying
   some strands and detailing others)

Anyway, the important thing is to render the general impression
of the hair and focusing on details on specific parts. If you try to
draw every strands, every individual hair, it’s gonna look cheap and as
far from realistic as it can be. It’s the same process whatever the
quality of the hair: straight, curvy, wavy, etc. You just enhance
different shadows and highlights in order to create different textures.

Don’t
forget either that hair follows a pattern on the head. It grows a
certain way and it’s different according to people. When you are working
with your medium brush (step 3), you have to pay attention to “the
direction” of the hair. Look at Jensen Ackles for instance:

And of course, don’t hesitate to use a reference picture. If you want to
draw realistically it’s essential. And it doesn’t matter if you draw
an OC. Your OC is a woman with long ginger hair? Google is your friend
to show you how ginger hair reflects the light and all the information
you need on color and texture.

When I draw artworks for The Life of Bucky Barnes, it’s a completely different method because here, I do draw the hair almost strand by strand. Basically:

This is a drawing I’m working on at the moment for The LoBB, it’s Steve. So first, I define the general shape of the hair, then I draw the line art, then I block the colors (usually far darker than Steve’s actual color) and the rest is just working slowly on the details and doing some color correction from time to time. I tend to draw the root darker but it’s closer to comics than actual realistic style.

Two styles, two different methods, two different rendering. 🙂

I hope I answered your question ♥ Thanks again for enjoying my art so much ^^