Let’s take a look at coloring in Photoshop. Create a layer underneath your lineart layer and lock the lineart layer. Now color in your lineart in the new layer. That’s pretty much straightforward. But now what… How do you blend and add shadows? Again there are a couple of ways to approach this. These are the ones I use.
1. Shadowing with opacity options:
The easiest way to shadow is to create another layer between the color and lineart layers. Let’s call this layer the “shadow” layer. Select the paintbrush tool and change the setting to your liking. Set the color to black and color in everywhere where you want the shadows to be. When you’re finished simply set the layer opacity to a lover setting. I usually set it to about 20 or 25. The thing with this method is that not all colors will look great with the same opacity settings. To solve this you need to use multiple shadow layers and set them individually. The same process works for highlights, the only difference is you use the color white instead of black.
2. Using the brush tool to blend colors:
This is basically the same as painting with real brushes but a little less organic. You simply need to take a darker color to what your base color is and start applying the shadow where it’s darkest. Now set the brush opacity to about 40 and color in between the base and darkest color. You’ll immediately notice that the colors blend a bit. Now choose the color picker tool and select the middle color and with the brush still set to a lower opacity start applying the color. Do this until you gradually make a good blend. This method takes practice and this is really a quick way of explaining it.

EDIT: One method has been removed from this tutorial, since it was not really an appropriate method to make convincing colors. Since I’ve written the tutorial I’ve learned a couple of new things and that was one of them. Sorry about that. Maybe I will make a new tutorial that teach some new approaches.
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