Bob Ross utilized the wet-on-wet oil painting technique, in which the painter continues adding paint on top of still wet paint rather than waiting a lengthy amount of time to allow each layer of paint to dry. Combining this method with the use of two inch and other types of brushes as well as painting knives allowed Ross to paint trees, water, clouds and mountains in a matter of seconds. Each painting would start with simple strokes that appeared to be nothing more than colored smudges. As he added more and more strokes, the blotches transformed into intricate landscapes.
Bob Ross noted that the landscapes he painted - typically mountains, lakes, snow, and log cabin scenes - were strongly influenced by his years living in Alaska where he was stationed for the majority of his Air Force career. He repeatedly stated on the show his belief that everyone had inherent artistic talent and could become an accomplished artist given time, practice, and encouragement, and to this end was often fond of saying, "We don't have mistakes here, we just have happy accidents." Ross was well known for other catchphrases he used while painting as he crafted "happy little trees". In many episodes of The Joy of Painting, he noted that one of his favorite parts of painting was cleaning the brush, specifically his method of drying off a brush, which he had dipped in odorless thinner, by striking it against the thinner can and easel. He would smile and often laugh aloud as he "beat the devil out of it." He also used a palette which had been lightly sanded down which was necessary to avoid catching the reflections of strong studio lighting.
When asked about his laid-back approach to painting and eternally calm and contented demeanor, he once commented: "I got a letter from somebody here a while back, and they said, 'Bob, everything in your world seems to be happy.' That's for sure. That's why I paint. It's because I can create the kind of world that I want, and I can make this world as happy as I want it. Shoot, if you want bad stuff, watch the news." After his death, Bob Ross Incorporated donated most of his paintings to charities and Public Television stations.