I use Mr Color paints but I think this will apply to most gloss white (and any gloss paint for that matter).
I typically prime my airliners with Tamiya White Fine Surface Primer. After priming buff out the primer with a very fine sanding pad or cloth. Or you can use paper towels. Using a white primer means that you can use fewer and thinner layers of gloss white.
Next, I air brush on the white. I thin it very much...more than I thin flat paints. I spay it on so that it goes on just a little wet. Not to much, though, because you don't want it to build up in spots or run. Keep moving and don't spend more than one or two air brush strokes in one spot.
Let it dry thoroughly. Any flaws or specks in the paint can be sanded out with fine grits of sanding pads or polishing kits. Just be sure to use light pressure. You just want to touch op the flaw...not remove a bunch of paint. Then go back over this with the very thin mixture of gloss white. Repeat this step as many times as necessary but you should have excellent results after the first or second touch ups.
Hope this helps