To make your pet realistic by adding shading, follow these steps.

Open your image and click on the magic wand tool. ()
Next you want to click on the white space around your pet.



Tip: If you have a litte space that won't select, like in between the legs, hold down the shift button while selecting that part, then click on the outside of the pet in the white space.

Next you want to invert the selection. Select - Invert. (Ctrl + I)

Then you need to take the dodge/burn tool. ()

Select a Circle(11) brush, and change the opacity to around 50, click on burn, and select midtones. Now you want to place the shadows on your pet, according to where the light would shine. Basically, it's just the underside of the pet, under the chin and such.


Finally, with the same settings, click on dodge and add some highlights to places opposite your shadows.

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