To create a nice perspective, you don't necessarily need a vanishing point. An atmospheric perspective can be created using various color tones, gradient fills and transparency.
This is perhaps the easiest form of perspective to create since you don't need precision or working with a ruler! However, it's still easy to make mistakes if you don't follow some simple guidelines. Let's try to draw a simple cartoon background using this special technique!
First, I have sketched various elements like a tree, some grass, a couple of hills and three mountains. I've also added a sun to complete the picture. Notice that the tree is on the foreground in this image.
In this drawing tutorial, I will modify all elements starting with the one in front. Then, I will gradually go deeper into the drawing to finish with the sky.
In this step, I have added a gradient fill effect to the tree. The parts that are exposed to the sun are lighter. Just follow the outline of the tree and you'll be fine!
Next, I have changed the color of the grass and the hills. Just use a dark tone for elements that are closer to the viewer and a light one for objects that are further.
Now, let's work on the mountains. The one on the left should be darker than the others since it's the closest one. However, the one in the middle should be very light, almost transparent. For both mountains on the left and on the right, make sure that the bottom is darker than the top (which is exposed to the sun).
To increase the atmospheric effect, I have added a couple of clouds (with a light transparency) to cover partially the mountains and the sun. You could even add some clouds behind the first two mountains to increase this optical illusion!
Finally, to complete this drawing, I have applied a gradient fill effect to the sky itself. This drawing may not be perfect, but it has been greatly improved compared to the first one available above. While the first one was strictly 2D, this one is clearly more appealing. Adding depth to your creation is quite easy with this technique!
I hope you enjoyed this simple tutorial on atmospheric perspective and don't forget to come back for more great drawing resources! Have fun!
External resources: How to draw perspective