There's no trick. Works the same regardless of what you're painting.
To avoid painting outside the lines (to avoid being sloppy), the general ideas are to ensure your paint isn't too thin, isn't overloaded in the bristles and then you paint close to the line on the first pass, then paint to the line on the second pass. This avoids a few problems, if you're a bit off you are erring on the side of caution and if there's a bit too much paint it doesn't flood over the line, lastly it also preps the area by wetting it, so when you go over it that second time, it's smooth and controlled, at least a little more so.
If by frosting the clear, you mean the cockpit, it shouldn't do that from the paint. Be careful with your dirty fingers (especially with paint or glue on them) because that will mar the finish. Super glue and plastic cement might cause some frosting, but if you keep the glue use to a minimum it shouldn't be a problem as anywhere the glue touches will be painted. If by frosting the clear you meant the clear coat you use for protection, then it's the same as always, leave the can of clear and the model in the room you're going to spray it for a while so it is all at the same temperature, shake the can well, spray at the 8" to 12" distance, light passes...that's passes, not sprits, not shots, not squirts. I think I'd just use a brush on clear though, it would probably look better if the "glass" wasn't covered in a coat of clear.
The primer should stick fine to the cockpit, the paint should stick fine to the primer, just make sure to wash it in warm soapy water. I think they use more mold release on the clear stuff, so washing is more important than it is on most of the modern plastic kits. If you don't want to start over, doing a protective clear coat should stop it from rubbing off, I'd think.
Needing to wash clear parts more than regular parts is probably the only useful bit of info here...:snicker: Did you wash the cockpit before painting?
