how to make aircraft look good?

It's the "junk" like you've mentioned that makes ones model look "good" like you've seen in the magazines and such.  Sure, weathering, and detailing isn't a must, it's a personal preference, as I'm sure you know.  If you are just wanting a good looking, well built model concentrate on construction, painting and finishing.  Fill all seams and gaps, and get all the parts attached according to specks as normal.  Then put down a quality paint job using freash paint with your airbrush and basically it's done.  But if you want to improve the realizm factor, go a head and try some minor weathering, such as streaked gun smoke stains near gun muzzles using pastel chalks, or a subtle panel wash using acrylics.  These are very easy to do, and with a little practice, you'll wonder why you didn't do more often with your models.  These two basic techniques can do wonders in enhancing your models appearance.  Some of the most respected master modelers in the hobby and film industry use these two simple techniques to "ohh and aaah" us.  Check back issues of FSM, and this forum for step-by-step techniques and methods.  We'll be glad to help! 

Welcome mchugh119

Here's a good source for basic weathering info:

http://www.swannysmodels.com/Weathering.html

-dave

Before "painting seams" and such, do some research. Does the prototype show this kind of effect? The F-22 is a new bird in the inventory and hasn't seen a lot of use yet. Remember, this is an aircraft designed for stealth operations. Big panel lines and stealth are not very compatible. Also, IIRC the Italeri model is an early prototype and was released about 1992 so there have been many years of design upgrades. Any stealthy aircraft requires attention to maintian its low radar profile. The B-2 was noted to lose some of its stealth when it got wet.

Here's a link to some real world F-22 pictures:

http://www.globalsecurity.org/military/systems/aircraft/f-22-pics.htm

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