Buddhist monks and even Dalai Lamas used to draw beautiful and complex mandalas both on canvases using pigments or on the ground using colored sand.
The beautiful ritual of the making of the sand mandala is quite famous. The most distintive part of the practice is that after hours and hours of piling sand to form the various details and elements, once the Mandala is completed it is removed as conclusion of the ritual. The mandala disappear in a vortex of colors, beautiful representation of the impermanence of reality.
However today mandalas are not used for initiation rituals only. Thanks to painted thangkas, Mandalas became a great visual aid for concentration and everyday meditation practice and today traditional mandala art is considered one of the most effective forms of healing and therapeutic arts.