Page Layout Tool. Handles appear in the upper left and lower right corner of each system.There are 3 ways:
1. Drag the lower right handle horizontally
Advantage: It's quick, and you can see what you are doing.
Drawback: It's unprecise, and you may inadvertently drag vertically.
2. Drag-select the lower right handle, and nudge it with the LeftArrow key.
Advantage: It's precise, and you can see what you are doing.
Drawback: It's slow.
3. Bring up the contextual menu in the handle (Windows: right-click ; Macintosh: ctrl-click), and select Edit margins. The Edit System Margins dialog box appears. Enter a number in the text field for the right margin, and hit Enter. If you are not satisfied, try a higher/lower number. Keep trying until you are satisfied.
Advantage: It's precise, and you can see what you are doing. And it's fairly fast.
Drawback: Not as fast as method # 1.
By The Way:
With the Mass Mover Tool you can control the number of measures in each system. Often it is good to have the beginning of each "section", "sentence" in the beginning of a system. If you try that philosophy, you will often end up with 8 measures per system (or 4 measures).
Try this (in Mass Mover Tool): Click a measure to highlight it, and hit the UpArrow key or the DownArrow key.
Peter
