There are several methods you can use to paint pumpkins on canvas. One common technique is to paint the pumpkin in its natural color in the beginning, and then add highlights in different hues. You can also use any other color combinations you like to paint the pumpkin, such as black with white highlights. Another choice is to decorate your pumpkin with a more abstract pattern. This can entail painting swirls or designs on the pumpkin or putting extras like leaves.