Canvas paintings -- especially larger ones -- can often be hung on a wall without a frame if they have enough presence. However, framing a canvas is relatively simple, and you don't need to take your art to a shop to get the job done. Most of the materials you need may be purchased from a frame shop or from an art supply store.
Measure the length, width and depth of the painting.
Purchase a frame for the canvas. Take the canvas with you to the store, if possible. Purchase a frame that matches the color and tone of the painting. For example, an old fashioned still life of fruit might be best displayed in an elaborate, wooden frame. A more modern and abstract piece may best fit in a sleek, minimalistic frame.
Purchase clips to secure your painting on the frame. Frame clips can easily hold a painting in place without damaging the frame. Off set clips are more secure, but must be screwed into the back of the frame and usually do not work with metal frames.
Lay the frame face down and lay the painting face down into the space in the back of the frame.
Fasten the clips onto the back of the frame. Follow the directions that came with the clips, which may vary among clip types.
Professionals often attach brown paper to the back of the framed painting to prevent dust from settling there over time. If your painting is a non-standard size or depth, you may need to take the painting to a professional framer.