How to Prime a Canvas for Acrylic or Oils

Priming a canvas for acrylic or oil painting is not difficult, and it's not even necessary if you are using  pre-primed store-bought canvases.

But if you have made your own stretcher bars or even just stretched un-primed cotton canvases over store-bought stretcher bars then it's very important to use Gesso to cover the surface of your canvas before you start with your paint.

When you have stretched your canvas, the next step is to prime it so you can paint on it. With a ready-made gesso suitable for both acrylic and oil painting, this is easy.

What you need: 

1. Acrylic Gesso (found at any art supply store) 
2. Wide Brush or a regular house painting brush
3. some water
4. a bowl and spoon
5. your raw canvas

Here's how:

1. Make sure you buy a gesso that's suitable for both acrylic and oil painting. This dries very fast and is painted directly on to the stretched canvas.
2. Shake the container very well before using. Do not skip this step!
3. Decide whether you are going to apply one or a few coats of gesso. One coat gives a rougher finish. If you are applying only one coat, use the gesso as it comes out of the bottle.
4. If you are going to apply several coats, dilute the gesso with some water.
5. Using an old, wide brush, apply the gesso directly to the stretched canvas in even strokes. Work from the top to the bottom of the canvas, in parallel strokes from one edge to the other.
6. When you're done, wash your brush out immediately with soap and water. Once gesso has dried on a brush, it won't come out.

Tips: 

1. A cheap decorating brush works well, but wash it several times before you use it as the hairs tend to fall out. If you want the brush to be thinner, cut off some of the hairs with a pair of scissors.
2. Instead of diluting the gesso, you can sand down the canvas between coats if you want a smoother finish.
3. Gesso thinned with water only, rather than gloss medium and water, tends to crack.
4. Gesso can also be used to prime hardboard.