Learning to paint on a canvas is not as complicated as it may seem, and it is not entirely different from painting on any other surface. In order to begin painting a canvas, some preparation is involved.
Canvas Preparation
Purchase a canvas of the appropriate size, or make one on your own. If you are going to make your own canvas, you may purchase the stretcher bars at any art or craft store. Tear a piece of canvas large enough to fit over the edges of the stretchers with room to spare on all sides. Lay the canvas on the ground and then lay the assembled stretcher bars in the center of the canvas. Pull the canvas over each side and staple the canvas to the stretcher bars, beginning from the middle and radiating outward. Staple down the corner of the canvas. Flip the canvas over and brush off any dust it may have picked up from the floor.
Now is the time to prime the canvas. This stretches the canvas tight across the bars and prepares a fresh white surface for painting on. This is a necessity if you are painting with oil paints because oil paints applied directly to canvas will eventually cause the canvas to deteriorate. However, if you are planning to paint with acrylic paint, priming the canvas is not a necessity. Be aware that if you do not plan to prime the canvas, the canvas will absorb more of your paint than it would otherwise. You will also need to take care to stretch the canvas more tightly across bars when you staple them.
In order to prime the canvas, mix two parts gesso with one part water and paint it on the front and sides of the canvas. As the gesso dries, the canvas will shrink (much like the way that clothes will shrink in the dryer) and pull tight against the stretcher bars.
Painting
Set up your canvas on an easel in a quiet place with adequate light. Adjust the easel to the appropriate height and angle it to your tastes. Good ventilation is important if you are working with oil paints. Begin the painting by applying the paint in a thin wash on the canvas. Build up in thicker strokes as you progress. Applying the paint in a thin wash will allow the canvas to soak up some of the paint and make a favorable surface on which to build your image.
You will probably wish to paint in sessions. If you are using oil paints, you will likely reach a point in which the canvas is too wet to continue and you will have to step away before you can make further changes to the image. Acrylic dries very quickly, but it is still a good idea to spend time away from the canvas to get a fresh perspective on your image.
If you find yourself stuck and not sure proceed, or if you feel that something is wrong with the image but you're not sure what, one technique to try is to turn the canvas upside down and then step away from the canvas and view it from a distance. What do you see? Check your color balance and look for elements on the canvas that are out of proportion.
Finishing
Your canvas may be framed by a professional if you take it to an art supply store or a craft supply store. A nice thing about painting on canvases is that a canvas does not need to be framed in order to be hung on a wall. You will probably notice, however, that the sides of the canvas look sloppy and unfinished. Try painting the sides of the canvas to match the image to give it a more finished appearance. Be careful when hanging the canvas on the wall that the nail does not poke the canvas. Even if it does not poke a hole through the canvas, a nail can stretch the material with time if it juts out against the painting from the wall.
