Click file, then "open" in the gimp toolbar. Select an image, example: My Pictures, image name example: "My F150". Open two images, one the "My F150" truck image and one the background you want to put the truck image into, use either "Scissors select tool", "Rectangle select tool", "Ellipse select tool", "Free select tool", "select by color tool" etc. from the main gimp toolbar to highlight the area within an open image you want say, "My F150" to copy and paste into another image say a background.
If you make a mistake and want to "undo" it, click on edit, then click undo.
It will help scale your two different images to appear to have the same size or if you want an image to be smaller or larger in your background by using "Image" on the top toolbar, then click "scale image" from that drop down menu. Say 1500 pixels width, hit tab and then Scale. The size of that image will scale up or down depending upon your desired size selection.
After you have highlighted an area of an image, Click image on the toolbar, then in drop down menu click "Crop to selection". Click edit in that new crop to selection image's tool bar then click copy within that drop down menu toolbar. Go to the image you want to paste it into, Click edit, then click paste in that drop down menu. Then click "file", "save as" and name your newly created image. ex: "New Signature".
The way I learned how to use this "gimp" image editor program was to just keep clicking on every toolbar option to see what happened, basically by trial and error.
That's

BAMA,
I told my friend about the free "gimp" GNU Image Manipulation Program when we were making our own paint skins for the online sim racing. The first thing out of his mouth was just as the picture you posted. A gimp suit.
