I'm going to use a friend's art for examples.

https://bwerecat.deviantart.com/art/Feeding-Instructions-727091684

For this once, can you tell what color the shading is? Pink (or purple), to match the background.

Meanwhile, this one: https://bwerecat.deviantart.com/art/Feeding-Instructions-727091684

Might have some brown or dark grey shading that's been overlayed or multiplied to match the colors underneath.

Another way some people shade is to *erase* the areas of the body that are being highlighted instead of shaded, although I'm not as on-par with that tactic as other types of shading.

For the best shading tips I have, It'd be best to not use the color black, avoid it as much as possible.xD

When shading use multiply! You can change your layer settings under the navigator!(Under layer opacity) Multiply should be there!

For blending, I'd suggest using Airbrush, Blur, or Watercolor(better for scenery). I don't suggest using the blending style for your shading though, it could look a bit messy(unless that's your style) x3.

You could PM me for more tips! I'll also link a video to an awesome shading tutorial(I still use it lol).

https://www.youtube.com/watch?v=AsHcI_W4LB4