To paint directly on the surface or canvas without an underlayer. This allows you to finish faster, and it is good for quick studies.
To apply a thick layer of paint on the canvas to retain the texture of the brush. Visible brush marks are very beautiful and unique and are only possible when using a brush loaded with thick paint.
Use a painting knife instead of a brush, which gives you a textured layered look.
Start your painting with a thin layer of paint to change the tone of your canvas. You can also buy a tinted surface to paint on.
To smear a layer of broken-up paint over a dry or a semi-dry layer of paint, and allowing the bottom color to peek through. Make sure to apply the “fat over lean” rule when using this technique.
To paint lightly over a textured surface with only a small amount of paint on your brush.