its bloody simple…
-add to shpere or any object a shader with this settings…
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-we turn the diffuse amount of the shader to zero, because we do not want any shading on our object
-set the luminous to samething like 1
-with the luminous color can we change the color of our object

and should be look like this…

-how lets make the outline… add a gradient and set the layer to luminous amount
-set the input parameter to “incidense a angle”

-open up the gradient editor
-add a extra key and set the values like this…

and should be look like this…

-if you move this key in any any direction --> you can make the outline thinner or thicker…
- now you can play around with other gradient to get different look
- example if you add extra gradient and set to diffuse amount and blend mode to Add
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- and set the key of the new gradient like this…
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[left]- or try a slope as input parameter of extra gradient and set it key´s like this
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enjoy !!
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