This can create a lot of dust so if you are sensitive you will want to wear a protective face mask.
After all the sanding and sawing you will get all the dust off with a wet cloth or just go ahead and run it under some water.
Note that I taped over the part of the gun that is the hand grip. I did not paint it at all because I didn't want to chance the paint coming off on people's hands as well as not wanting to agitate skin allergies or anything like that.
Using the silver as a base had an unexpected result. I used the sponges to apply the blue paint. With the first stroke my royal blue mixed with the silver and to get the light blue panels you see. I actually liked how it looked so I just went with it. But if you want to make sure that doesn't happen then use the masking tape to cover up the sections to want to be different colors. If the tape takes any paint off you can touch up later.
Make sure to let each layer dry completely.