Okay...hope this is clear...I threw it together...haha
STEP 1 - This is in the hair room, actually creating the tuft of hair on Doc's head.
STEP 2 - This is the default hair color, which is really, really blonde. It's good to check it with a render before proceeding, to make sure there are no stray hairs sticking through the eyes or ears.
STEP 3 - Next (making sure the hair is selected), you go into the Material Room by clicking the Material tab at the top. It defaults to the Simple Material Room option.
STEP 4 - We'll switch over to the Advanced Material Room by selecting the Advanced tab. Notice over on the right side, under Hair, you'll see three colors...Root_Color, Tip_Color, and Specular_Color...or greenish beige, a cream color, and a gray. This is where you choose your hair color in the Material Room, and you can keep tweaking it until you get it like you want it.
STEP 5 - In this example, I chose a reddish dark brown, a light brown, and I left the specular color.
STEP 6 - Render to check the results. In this case, I ended up with a very light brown, so this gives you an idea of how much play you have in choosing colors...you can go much darker than what I've chosen.
STEP 7 - If you want the hair to "lay down" on the head more, you can choose to run dynamics....at the top, pull down under Animation, and choose Recalculate Dynamics (making sure the hair is selected), and select All Hair. Some hair styles you might want to be sticking up, so just choose to do this if you want the effect.