Tubes

I pick a blue color and create a new layer on top of everything else. Then with a light airbrush tool, I add some glow on a layer set to add glow.

Orbs

For the larger orbs, I use the gradient tool, setting it from color to transparent. I don't drag the gradient all too far, it's just to give the orbs a little light.

The glove

Creating a new layer on top of everything else, I draw some lines on his glove. I'm going to use the same technique as I did with the screens, copying the layer and adding Gaussian blur on top of the lines, to give a slight glow effect.

The rings

I want to add some glowing blue rings to the chair, serving as legs for it. I do this by creating a new layer, and set it to overlay. I then draw in some rings using pure white. Duplicate the layer and use Gaussian blur to soften it op a bit, and set the new layer to color dodge. Lastly I add a light sprinkle of white using the spray tool.

All done!

And that's it. I know that my use of the many many blending modes are limited, but I hope it taught you a thing or two about how those can be used. Below you find a time lapse of the coloring process, which has taken no less than four hours and thirty minutes. And that's without all the planning, sketching and shading of the character. In total this has taken about fifteen hours or so. I hope you enjoyed it!