Alladin,

The only sure fire way to keep the plane clean is not to fly it.

It's just the nature of the beast when you fly glow two strokes. But there are a couple of things that might help. Make sure you have your exhaust pointed in a direction least likely to deposit the oily exhaust on the plane. You could use an exhaust deflector (a rubber extension available from your LHS) to exhaust further away from the plane, although there will be some power loss. Also, make sure your engine is not running excessively rich. Other than that, there are a few threads here that go in to the best methods to clean your plane after flying. I use a mix of 409 and alcohol - there are others that work just as well. I also like to use Monokote cleaner/polish from time to time -it works on all coverings and restores some of the shine to your finish. I might of missed something and I am sure someone else may have somethoing to add. Hope this helps.

Steve