Riotz,
In addition to building plastic models, I build and fly RC aircraft. Personally, I wouldn't use paint to do your project. The problem with paint is that you are placing the paint over a plastic film that was used to cover the airplane. That plastic film will shrink and expand with temperature changes causing wrinkles in the smooth covering. Normally the wrinkles can be made to go away with the application of a little heat from a heat gun or iron. Both of these tools are used by RC modelers to apply the covering to the balsa structure. Once you start doing that, you will probably ruin your paint job. Also, you didn't say what type of engine your model has. I am guessing that it is electric. If that is the case, you don't have to worry about your paint being fuel proof. If it is a glow engine, then you have to have a paint that is fuel proof. Glow engines tend to be messy and usually result in part of your airplane being covered with fuel/oil that was blown back from the engine. There are some really good scale RC modlers that can do realistic paint jobs on their models. They use latex paint on airplanes that are covered with fiberglass and use gas engines. The gas engines are easier on the paint and the paint is going on a surface that is solid and stable and not subject to develop wrinkles with changes in temperature.
You have two other easier options. The plastic covering used on model RC airplanes comes in many different colors. You can get colors that match your design and cut them freehand. The covering has an adhesive on the back. You simply lay your pattern over your base color, apply a little heat and this bonds the pattern to the base covering. I have seen some good modelers do some really complex patterns this way. Two of the more common plastic covering brands are Monokote and Ultrakote.
The second option is to do your design using your computer and a graphics design program. Your are going to need one that will convert your design to vector graphics (I think that is what it is called). In any event, you want to be able to take your completed design to a sign company or someone who has a vinyl cutter. The cutter uses your design image and cuts a vinyl pattern. The type of vinly is commonly used to make lettering for signs. The vinly comes in hundreds of colors and also has an adhesive on one side. You spray windex on your base color, position the vinyl where you want it, use a credit card to smooth any bubbles out and let it sit for a little while. Your vinly trim piece is now bonded to your base covering. The windex will enable you to position the vinyl trim piece without fear of having it bond to the base covering. The windex evaporates bonding the two pieces together.
Finally and after you have done all this work it's time to fly. If you don't have any experience flying model airplanes, do your test flights on something else. It is not easy to fly a RC airplane and most people will crash on their first attempts. The most common problem is that people forget that an airplane flying away from you has the controls and control imputs be as they would work in a full sized airplane. Once the airplane turns towards you, as you look at the airplane now, the control imputs are reversed. Things happen fast when you fly a RC model airplane and the imputs have to be instinctive. If you have to think about which way to move your transmitter controls, you are going to crash.
Flying and building model RC aircraft is very fun and rewarding but like anything else, requires practice. I would hate to have you spend a lot of time and then crash your airplane.
Hope this helps,
Chuck B.