01. DRAWING HAIR
(Forewarning: I don't draw hair 
anymore so this is from memory on
how I used to do it so, please
forgive me if it looks bad.)

A. HAIR BRUSHES

Hair Brush by MissMalefic (deviantart)

Fiber Brushes by GrindGod (deviantart)

B. DRAWING THE HAIR

1) Get your color palette for your hair.

(This can work for any hair color, I just chose brunette for this example.)

2) Using the darkest color, begin drawing the shape of the hair.

3) Add hairs around the basic shape to add flyaways or singular hair strands.

4) Using a lighter color, use one of the fiber brushes to create the texture of the hair 

5) Using the second lightest color, draw on the shadows of the hair and change the blend mode to multiply. Using the smudge brush, start to blend it out. (If the color is too harsh, turn down the opacity.)

6) Using the same color, use a fiber brush to make hair strands where the shadows are. (This will help blend it.)

7) Using the lightest color, draw on the highlights of the hair and change the blend mode to lighter color. Using the smudge brush, start to blend it out. (If the color is too harsh, turn down the opacity.)

8) Using the same color, use a fiber brush to make hair strands where the highlights are. (This will help blend it.)

9) Using white, draw a small line on the center of the highlights and change the blend mode to overlay. Using the smudge brush, start to blend it out.)

And you're done.

Example 1:

Example 2:

02. HAIR STOCK

A. DOWNLOADING THE STOCK

You can find multiple FREE hair stocks on deviantart, but the ones that I use require payment. So, I'll be suggesting some of my favorite free ones.

FREE:

Hair Strands Stock
Hair Stock PSD files
Hair Stocks
by CindysArt (deviantart)

PURCHASE:

PSD HAIR STRANDS 1-51 by MrsDebora

(This is PSD Hair Strand 8)

B. USING THE STOCK

1) Open the PSD file in photoshop and chose the hairs you want to use. Move the hairs to your image. DON'T FORGET TO COVERT THEM TO SMART OBJECTS! (I taught you better.)

2) Image > Adjustments and use whatever adjustments to make the hair match the model's natural hair. (I normally use Brightness/Contrast, Exposure, and Color Balance.)

3) Use CMD + T (Mac) or CTRL + T (Windows) to turn on the transformation tool, and click on the warp button.

This will give you the ability to move your hair strands in unconventional ways.

4) Add as many hair strands as you need to complete the hair.

5) Group all of the hair layers, and add a clipping mask on top of it.
(Right-click layer > Create Clipping Mask)

6) Just like we did in the hair drawing, place a darker color on the shadows of the hair (and wherever you want shadows) and change the blend mode to soft light. Use the smudge tool to blend.

7) Add white on the highlights of the hair and change the blend mode to overlay. Use the smudge tool to blend. 

8) Use a dark color and place it where the hair comes from the head to create a shadow from the head. Change the blend mode to overlay and use the smudge tool to blend.

(This will add dimension to the hair and not make it look stiff.)

And you're done!