The coloring page features two cars – a gray one with blue stripes and a green one – parked side by side. The gray car has its hood up, and behind it is a beautiful blue sky. To make the scene more vibrant, I would color the gray car with a dark blue, the blue stripes a lighter blue and the green car with a rich, deep green. The sky could be filled in with a bright blue, which will help the cars pop against the backdrop. I would also add some white and yellow highlights like the sun's reflection to make the sky complete. This would add a bit of life and movement to the coloring page.