To edit the properties of a graphic object, double-click on it or right-click on it (to access its context menu), and select Appearance…. A dialog like this will be displayed:
The Fill tab is not present when editing lines, polylines and curves.
The Line tab allows you to edit the appearance of the line itself (for lines, polylines and curves) or the outline for the object (for polygons, rectangles, closed curves, and ellipses). You can select the Color, the Style and the Width (and for Lines and Polylines, the Line Head). You can also make the line Transparent (which would only make sense for polygons, rectangles, closed curves, and ellipses).
The Fill tab (which is not available for lines, polylines and curves) allows you to change the appearance of the fill for the object.
The fill consists of a background and a foreground. The Foreground Color is superimposed on top of a Background Color according to a selected Pattern. By default, the background is transparent.
The Locking tab determines what you can do with the object:
If the Allow Move and Allow Rotation boxes are checked (the default), you can move and rotate the object.
If Allow Scaling is checked (the default), you can resize the object. For objects that can be scaled, if Lock Aspect Ratio is checked, the object keeps its aspect ratio when it is resized.
If Lock Appearance is checked, all of these options are disabled (you cannot move, rotate or scale the object).
Learn more about: