In this tutorial I am going to show you the basic steps to create a stylized spaceship sprite similar to what I have posted before. This is not going to be a step-by-step tutorial oriented to one or two particular programs but instead I will describe the basic processes to achieve a similar result, no matter what programs you are using.
Step one: Create a basic spaceship in 3D.
Model a really simple spaceship using basic colors and textures, create a dim light directly above the spaceship with soft shadows. Place the camera directly above the spaceship. Make sure the specular is not very bright, and render it. It may be best to have the camera set to an orthographic lens setting (not perspective).
Here is similar to what you should have:
Step two: Draw an outline.
Using your favorite image editing software, open your spaceship image, create a new transparent layer, on the left half of the new layer (or the right, doesn't matter), trace the outline of your ship with a one pixel wide, sharp edged brush or line drawing tool with a solid black color. Also trace any prominent details of your spaceship (engines, hull sections, etc).
You also may want to add a few lines where plates and sections connect.
Next duplicate the layer and flip it, so both halves of the spaceship are decorated with the black lines. next, merge it down so that you have two layers, one with your spaceship, one with your black lines.
You should now have two layers and your spaceship should look like this:
Now create another transparent layer.
Next with a solid, one pixel wide white brush or tool, draw simple two-three pixel wide windows on one half of the spaceship (right or left half).
Duplicate the window layer and mirror it and merge it down with the other half of the windows.
You should now have three layers and your spaceship look similar to this:
Now duplicate the windows layer, and colorize it to a color of your choosing, but of a high saturation, I chose blue.
Now blur the new colored windows layer 2-3 pixels.
Now move the new, burred, colored windows layer below the white windows layer and duplicate it repeatedly until the glow becomes visible enough, your spaceship should look similar to this:
You should now be done, I hope this tutorial was useful to you, thanks for reading!