Making a canvas stretcher and stretching your own canvas to paint on is super easy and a lot cheaper than buying them! You can make them whatever size you want!
First, you cut down some pine studs and add a bevel edge to make a frame, then glue your frame together, and staple or nail gun the corners together. Depending on the size of the canvas, or how heavy your painting media is, you may want to add support rails across the middle of the frame.
Second, you stretch the fabric around the frame. Put the fabric on your work surface first (I use the floor lol), then lay down the frame, bevel edge down. Staple the fabric to the back of the frame, or to the inside bevel if you're feeling adventurous. There are helpful tutorial videos at the bottom of this post.
Third, smooth those corners down, and staple them.
Fourth, if there are wrinkles in the fabric, spray with warm water and let dry. If there are no wrinkles, you can skip this step.
Fifth, gesso that bad boy! Let it dry, and you're ready to paint!!
And with a little practice, they will look professionally done, like mine:
This time, I used super-thick muslin fabric instead of canvas and primed with clear gesso. Look at that natural beauty, those tiny speckles! Love it! You can use most any kind of fabric, but most people use canvas, cotton duck or burlap. And for gesso, you can use anything from cheap Kilz primer to the priciest gesso at Hobby Lobby!
Here are a couple tutorial videos on stretching canvas:
And here's one on how to get those pesky corners just right:
