The canvas is the background of your drawing. You can change the size of the canvas, the canvas fill settings, and make changes to the grid settings.
Click the Canvas button on the toolbar.
You will see the canvas options on the editing panel.
Click the Fill pull-down menu to choose how the canvas should appear. You can choose a solid color, a gradient, or a file or pattern. See the Gradients and Fill with File or Pattern for more information about these options.
If you plan to export your image as a PNG or GIF and want the background of your drawing to be transparent, make sure the Fill check box is not checked.
The current size of the drawing is shown under the Dimensions heading. Use the Dimensions pull-down menu to change the units of measure for your drawing. Click the Edit button to change the size of the drawing.
Check the Grid box to show or hide the grid. The grid can be very helpful if you are trying to align objects in a drawing. See the Grid Settings topic for more information about the grid.
If your canvas is filled with a gradient, file, or pattern, use the Fill Controls check box to show or hide the controls for gradients, files, and patterns.