You can get a nice even coat with a spray can. When I first came to the Hobby I prefered Tamiya Cans. If you can get yourself an airbrush, I would highly recommend that( only if you are planning to stay in the hobby). You will be able to do alot more and alot easier.
I am not sure how you could do the dust with a spray can, possibly just a quick spray.
Try the paining forum, those guys are really good at this kind of stuff.
And,
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