Light painting involves a slow shutter speed and a continuous light source. You can either capture all of your light in one shot or do compositing techniques like the images below. Each image consisted of about 5-6 shots, merged by using layer masking. You can see the tracing effect this adds to the image. There's a highlight streak all the way down the truck along with deep shadows from where the light was ineffective. With an extra pass focusing on the tires you can achieve