The surface of Saturn is beige, with pale bands of gray and yellow. The gas giant is often depicted in vibrant colors due to image processing meant to highlight certain properties of the planet, but in its natural state, Saturn is very light-colored, almost pastel.
Exaggerated color depictions of Saturn are due to a process called false color. False color images of objects in space help scientists visualize data, but they have little to do with the planet's actual appearance.
Saturn does not really have a "surface" the way the Earth or Mars do; the gaseous layers of Saturn just get denser towards the core, with no clear boundary where the atmosphere ends. Scientists call the outermost layer of Saturn the surface for ease of understanding.