State of the art
Re-creation
Pick a part of a detailed piece of art - a familiar painting, for example. Then, choosing whatever medium you prefer (paints, coloured pencil, pastel, etc.), recreate your chosen area. You can choose to do it badly on purpose, choose different colours, leave parts out, do the work with your non-dominant hand, use a different style of drawing. Do whatever you choose, so long as you don't do a faithful recreation.
Gamification
Choose some rules before you start to guide how you go on. You could, for example, assign colours to the numbers on a die, and roll that die to choose your starting palette and/or how or when you change colours during the creation process. You could write down the types of media you have on separate slips of paper, fold them up, and choose one or two at random to guide what you create with.