Adding Text to Existing Aircraft Texture

Hi everybody! I've been reading through many pages of this forum for an answer to a basic question. Hope someone can help.I would like to write some text on the side of the default FS2002 Cessna 182 airplane. I have PhotoShop and was just wondering what the steps would be to accomplish this. I think I need to extract the 'mip-maps' with the Image Tool, add the text in PhotoShop and then run it through the Image Tool again. Does anybody know if this is how it's done and in what format I need to save the image files in?Many thanks for your help ...