How to color over grayscale

When coloring over grayscale the gray serves as your guide. Think of it as an adult color by numbers without the numbers. Instead the darkness or lightness of the gray tells you how dark or light a color to use and where to apply it. Simply put, light colors over light grays, dark colors over dark grays and medium colors in between to seamlessly blend light and dark. 

Some points to keep in mind:

• Apply your dark colors lightly to begin with. It's easy to keep making them darker but it's not very easy to lighten them. 
• Even if a part of your uncolored picture seems extremely dark you can and should still go over it with a dark color. It will make it pop and really help bring your image to life.
• You can go heavy with your lights right away, if you wish.
• You can start by doing your lights and then your darks or darks first then lights. Either way is fine and you'll likely switch back and forth a lot as you find spots you want to touch up along the way!
• When you apply your medium colors don't be afraid to color right over your already applied lights and darks (e.g. if you are coloring fur) so that you manage to nicely blend everything. You will find that the lights and darks show through your medium colors. It's not to say that you should cover everything with your medium color but instead that it's ok if there is overlap where needed as it will help with the blending and the detail will not be lost. You can see an example of this in the leaves and water drops of the ladybug picture below. 
• It doesn't have to be perfect. You will be amazed by how helpful the grayscale is not only in guiding you but also in enhancing your final picture. 

Here is a little cheat sheet I provide at the beginning of the "Beautiful Creatures" grayscale coloring book: 

Grayscale coloring in action
Now, watch these two time-lapse videos and watch how I apply my colors based on the darkness or lightness of the gray. As I apply the colors you will see the image come to life

What mediums should I use?
Colored pencils are the go to medium for coloring over grayscale but you are welcome to use whatever you prefer. Consider the grayscale as a guide for creating your own artwork. You can aim for a photo realistic result by using colored pencils or a more abstract result with oil pastels or acrylic paints. What's important to remember is that generally you want a medium that you are able to blend because you are trying to capture those various levels of gray and transition from one to the next somewhat seamlessly. Therefore, standard markers are not ideal but the blending markers can work.

If you are just starting out coloring grayscale then I would strongly recommend colored pencils as your main medium with others such as gel pens and fine markers for detail work (e.g. whiskers on a cat). 

How do I capture all those little details in a picture (e.g. water drops)?
What is wonderful about coloring over grayscale is that those little details will show through your coloring and help bring detail and definition to your final piece. Of course, you can help to make it more impactful by accentuating these details when you color but it is not necessary to perfectly color every single detail. 

For example, in the ladybug image below there are several water drops on the leaves. This seemed to be a daunting task. I thought I would need to carefully color each drop and then color around each one very carefully. Needless to say, it felt like the relaxation that comes with coloring was about to totally evaporate! However, to my great surprise, it was far easier and made me look way more talented than I expected! Basically, here's what I did:

• Chose a dark blue pencil & a white pencil
• For the handful of large drops I took the time to carefully color the darkest area with the blue and then highlight the rest with the white. 
• For the rest of the drops I just quickly did a blue dot and a quick spot or semi-circle of white for each drop. I really wasn't very precise. 
• Next I started coloring my leaves with colored pencils. Here's where I was thinking things would take forever. I thought I would need to color around each drop but I didn't! Instead I colored right over the drops and the details of the drops came through. In fact it looked more real because it was like the green of the leaves was coming through the water drop, as it would in real life.
• Then I used a blending pencil over all the leaves to smooth things out and the water drops continued to hold their detail and definition. 

Coloring Book: Beautiful Creatures
Colorist: Nicole Stocker