Soon after I left college, I worked at a storyboard house in Soho, London called Helicopter Studios. Most jobs were for the advertising industry and were usually divided among multiple artists. It was an essential skill to be able to adjust your style or match someone else's. Later on in my career, I used this skill to develop different styles to suit each project. In the case of Twisted Metal: Black, I switched to pen and ink to match the darkness of the subject matter.
Most of the sketches were delivered in black and white, and for those that were taken to color, I used Photoshop for the very first time. Up until then, everything had been markers, ink, and paint. This was much cleaner and less stinky.