When you are done, save the finished project as a GIMP XCF image as before. This retains all the different layers so that you can work on them some time later if you need to. You are now also going to create a few versions of the texture to use on your SketchUp model. These can be in TGA, TIF, or BMP format.
When you buy an asset, you want to know that you can use the asset straight out of the box. You also need to know you can modify it easily in the future, should you need to. An asset is exactly what the name implies—an asset to you or your company. It holds value and is stored for later use again and again. In order to make things easy for whomever ends up using your asset, you should name the textures and meshes something easily recognizable. Texture names should follow the format:
asset_feature_size.format
So for a car asset, you might name the headlamp texture, sized at 256x256 pixels as
astonmartin_headlight_256.tga
For your Pallet asset, you will be...