You can edit the Toolbar's style and bitmap size in the properties window.
Click on the “Edit tools...” button to edit the toolbar buttons. Use the “Add” button to add buttons to the toolbar; enter the label, an optional name and help string. You can use numbers or variable names as the button id. If you use a variable name, you have to provide extra code in the generated source code.
Choose the type of the button: Normal, Checkable or Radio.
You can move toolbar buttons with “Up” and “Down” buttons.
You have to enter two bitmaps, one for normal status and the other for the pushed status.
Refer to the section called “Specifying the path of bitmaps” for bitmap path specifications.