Corel Draw is a good program to make something like this. There are two basic file formats. Bitmap and vector. Bitmaps are like pictures with each tiny pixel a certain color, like your TV or photograph. Vector based images are more like cartoons. An outline with a color fill. Some graphic artists can make real detailed vector based pictures that almost look like photos but that is not important for our use. For making patterns for film or solid color paint application, vector based images are what we need. The nice thing about vector based images is that they can be scaled without increasing the file size. They also retain their shapes without jagged edges. Enlarge a small bitmap (jpg, bmp, gif, etc) and the edges become jagged and the appearanc becomes "pixelated". The file size would also be huge if it were the size of a wing. Corel draw has or at least used to have a trace function that tries to automatically make a bitmap file into a vector based image. For something like the picture you showed it works very well and requires minimal correcting once done. Once you learn to use a vector based program you can also easily trace the picture that you provided yourself making your own vector based file fairly quickly.
Once you have the basic drawing you would then have to expand the base colors like the white and one edge of the orange etc to allow for overlap of the film. As each color piece is a seperate object in the file they can be layered one over the other, so that the actual size pieces can be drawn and still show the finished product like your image. The bigger problem is how to then print out your patterns to make use of them as a template. You might need a large format printer that prints from a paper roll or you would need to tile the printing and tape pieces together. Of course if you really go all out you can use a plotting cutter to cut out your plastic covering for you. (Thats what I want
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Stuart