The goal of this tutorial is to give you some insight into my process and to show how you can achieve a believable illustration using color and value as opposed to concentrating on rendering.
The intial lay-in
For most of the painting I keep it zoomed out to 25% so that I can see the entire piece as I am working. Sometimes I will zoom in to 50%, but I try not to zoom in any more than that. If you work at 100% you will not be able to see how the painting looks as a whole, and will often times end up over-rendering. Working at 25% will also help you create a more loose painting. Another helpful tip is to constantly flip the image so that you can better see your errors and how your composition is working out. I usually work for a while one way, flip the image and paint on the flipped version for a while, and then go back and forth until I am finished painting. Sometimes I flip the image upside down as well.
I like to start my paintings by laying down a basic colored background and large silhouettes. At this stage I am using a large brush and am only concerned with shapes and composition. The brush I start with is a Photoshop default with opacity set to pressure.
After establishing some basic colours in the first stages I will then go back and tweak the colours more to my liking.
Here I wanted some warmer colours to give you more of a sense of a sunny day. I hit ctrl+b to bring up the color balance menu. Here you can use the sliders to change the highlights, mid-tones, and shadows. I will also change the levels in conjunction with the color balance.
I also wanted more of a "glowing" effect on the man's jacket, so I decided to use color burn. Most people will tell you to never use the burn/dodge tool, but if you know how to use them they can be a great tool. What I do, instead of using the dodge tool, is to set the actual brush's setting to "color dodge" from the drop down menu.
I want a yellow/orange glow, so I pick a darker version of the colour that I actually want. This way you can build up the glow slowly. After I am pleased with the new color scheme I continue blocking in shapes, but still leaving things loose
Now I start to refine things a bit more and add in the details of background and middle ground elements.
I added some shoes to the guy on the left, but decided that they were too distracting, so I let them fade off into shadow. One thing to really pay attention to are shadow shapes. They can really help to bring a picture to life and to also suggest form without having to really paint the entire image.