Basic Color
I will be using Suzanne for this tutorial
I use CTRL + 2 to add a Subdivision Surface Modifier with 2 levels – applying the modifier
I right-click and choose shade auto smooth
I use the Z-key and go into material preview so I can see my shader
I split my viewport and open the shader editor
I make a new material and rename it
I add a Shader to RGB node between the Principled Shader and the Material Output [Convertor]
This node only works in Eevee
It is used to apply additional effects to the output such as a color ramp
I then add a Color Ramp between the Shader to RGB and Material Output
This will allow me to control the color shading on the object
I change the interpolation to constant because I want a sharp line between the multiple colors
If I move the white color stop, I can now see the effect on the object
I change the black color stop to a dark red and the white color stop to a bright yellow [#62171F #A7840D]
I can also add a third color stop and make it a midtone blue [#4F7081]
This will give me multiple steps to the colors
I use the Z-key and go into Render Mode
Under the World tab, I change the color to a lighter tone
I add a sun light and position it
I adjust the color stop positions
As I rotate the sun light around I can see the shader reacting
Outlines
For the outline, I will add a new material and change the Principled Shader to an Emission Shader
I will leave the color white so it is easy to see the effect
In the Settings Panel, I check backface culling so I can see the material
With Suzanne selected, I add a Solidify Modifier
Under the Normals Panel, I flip the normals and choose high quality
Under the Materials Panel, I change the material offset to 1 so I can see the emission material and I change the thickness to a negative number [-0.02]
I can now change the Emission color to whatever I wish