Set any of the following options in the Property inspector:
ImageField assigns a name to the button. Two reserved names, Submit and Reset, tell the form to submit the form data to the processing application or script, or to reset all the form fields to their original values, respectively.
Src specifies the image you want to use for the button.
Alt lets you enter descriptive text in case the image fails to load in the browser.
Align sets the align attribute of the object.
Edit Image starts your default image editor and opens the image file for editing.
Class lets you apply CSS rules to the object.