The answer actually depends on the canvas that you purchase. Most, if not all, canvases that you buy at your typical craft stores are already primed for acrylic painting. If the canvas is a bright white color, it's ready to go!
This is one of many reasons I recommend that you paint in some background color first around whichever object you are painting. That way if your paint does dry on canvas, you can very easily blend into the dry background colors to re-wet those areas and continue with your still life.
Make sure you buy a bottle of gesso that is suitable for both acrylic and oil painting. This dries very fast and is painted directly onto the stretched canvas. Stir the container very well before using.
Usually either Burnt Umber + white, Raw Umber + white or Yellow Ochre. For the absolute beginner, I recommend using Yellow Ochre. Why? It's usually included in most beginner sets and can be used diluted with a little water.
1. Always Paint from Dark to Light. A common strategy for approaching a painting, is to begin with the darkest darks, and gradually progress through the midtones to the lights, adding your highlights right at the end.
The first step in the underpainting process is to choose a color. As mentioned, underpainting is most effective when painted in monochromatic tones. Many artists use darker tones, such as burnt sienna, raw umber, or ultramarine blue to achieve the most significant effect.
Using the wet-on-wet method, you apply a layer of liquid white to a canvas prior to painting with oil. It is easier to achieve sharper and more vivid colors by painting on wet canvas.
Priming Your Canvas
Take a stretched canvas, put some gesso in a bowl or on a paint palette, then use your brush to evenly cover the canvas. Let the gesso dry and then do 1-2 more coats for the best results. Once it dries, you're ready to paint.
Painting dark to light is the most recommended strategy for beginners and for experienced painters. This approach is almost mandatory for oil but acrylic is more flexible. That approach is valuable for 4 reasons: The dark basic layers will create the illusion of depth.
Oftentimes, though, beginning artists paint the subject first and then don't know what to do with the background. To avoid that problem, paint the background first.
Using acrylic paints (the easiest one to use) you are able to change the color of the paint (both dark and light). Paintings can be done in any environment, so there are no strict rules as to what they must be done. A lot of artists paint a mid-tones in to light paint mid-tones to light.
If you want your colors to stay vibrant and last longer, priming is essential. To Prepare a canvas for acrylic painting is a straightforward process. You need to apply gesso normally in three coats, where you sand them in between after they dry out.
In the case of powdery or unstable gesso or paint layers, you may have added water to them over time. As a result, acrylic binders are spread, which causes them to become less able to firmly adhere to the painting surface, resulting in flaking, cracking, or a powdery appearance.
The most popular surfaces for painting with acrylics are canvas, wood, or paper. But once primed with gesso, acrylics can be painted on almost any surface, such as fabric, clay, or even your old vinyl records!
What are the alternatives to gesso? You can prime a canvas with acrylic mediums, clear gesso, or rabbit skin glue. If you work with acrylics, you can also paint directly on raw canvas without priming it first. Oil paints require a primer to protect the canvas from the linseed oil found in oil paints.
Answer: When you buy a stretched canvas from a store, it's usually already primed, so you don't need to apply any extra gesso.
The best comparable alternative to Bob Rosses' liquid white is “magic white” that offers very similar performance at a very similar price point. You are usually able to mix a white paint with a suitable oil medium to get similar results too but most people prefer to just purchase a pre-made liquid white.
Underpainting is a painting technique made popular in the Renaissance in which you create a monochrome tonal rendering of a work before applying the full range of colours. Underpaintings are most often executed using browns, such as umbers and siennas (known as Imprimatura), or black-and-white (known as Grisaille).
Broken color refers to the technique of building up layers with different colors on the canvas in a way that allows previous layers to remain visible. This usually involves painting with small dabs of color, leaving gaps in between.
For acrylics, an underpainting is especially useful. Since acrylic paints dry quickly, an underpainting can be developed and layered upon in a short amount of time. Semi-transparent washes can added on top of the underpainting without waiting long periods of time for the underpainting to dry completely.