When you are trying to become a master the 3D Rendering software or tools, then there is only one thing you'll need to consider the most,  Don't do a bad render. Polish 3D artist Łukasz Hoffmann shared his best tips and tricks to do the best 3D rendering when it comes to cars.

Start with Simplicity

When modeling, try to maintain a simple shape and focus on proper curve lines. Cut out the details only when the main shape is established.

Use Fresnel Shaders

Fresnel Shaders for best rendering

When you are creating a car material, you have to keep in mind that, real car material paint is a combination of a few color layers. Always try to use complex colors and include multiple basic shaders. And when you are doing so, try to use the freshnel (it is a frequent angle). It'll enable you to blend between the shades and at a specific angle. You can also implement a specific type of noise algorithm which is called procedural Voronoi and what it'll do is, it'll compute 1D, 3D, 4D Voronoi noises and returns the real locations of the nearest points. Or you can also add a similar texture to normal shader channel to create metallic shade/flakes effect. 

Fresnel Shaders for best rendering

Choose HDRI wisely

HDRI (High Dynamic Range Imaging) can be used in order to sharpen and accentuate the shape of the car. My best pick would be High contrast HDRI. What it'll do is, increasing the color punch and enhancing the reflection among the curvature of the car. Always try to use the 32-bit HDRI to get the right color information for your sense. For this task, the simple studio HDRI is worth doing the best job for the most car scenes.

Additional Lighting

Using additional lighting for better car rendering

If the environment is not looking as realistic as you want despite using HDRI, then use additional light sources in the scene. But make sure to implement that much of light that will make sure it'll emphasize the shape of your car. And then set up a rim light which will pop out the silhouette of the car. 

Use Image based lighting

Using Dome light is really a nice way to add much more color and realistic look to a scene. Dome Light let you allow to adjust the exposure without any clipping. Otherwise, the colored section of an image can seem very black and white-ish, not letting colored data not pop up. It makes both the car and the image look dim and ugly. 

Consider composition

You can without much of a stretch tilt your camera to include a sense of movement in powerful and dynamic shots, put a vehicle in an intriguing place with a pleasant color palette. While making a whole scene try to isolate first, the second and third plane, and lead the viewer's eye with focal points & guidelines.

Slope any edge

Slope any edge in rendering

Don't ever forget to slope any edges in the time of modeling a car. Even a perfectly sharp edge looked by the naked eye isn't actually perfectly sharp. Especially adding a precise and narrow bevel on a refractive element like light defuser will give it a really realistic and high-quality light reflection.