A floating measure must be based on a “real” 
 measure. For most purposes, then, you’ll need to create a “scratch staff” 
 on which to notate the actual contents of the ossia measure. You then 
 choose “hide staff” in the Staff Attributes dialog box (see Hiding staves for 
 full instructions).
        
        
            - Choose View > Page View.
 
            - In a scratch staff, enter the music you want 
 to appear in the floating ossia measure.
 
            - Choose Window > Advanced Tools. 
  
 
            - Click the Ossia tool  
. 
            - Double-click the spot on the page (in Page 
 View) or double-click the measure to which you want to attach the floating 
 measure (do not double-click a measure on your scratch staff). 
 The Ossia Measure Designer dialog box appears.
 
            - Select whether you want a measure or page-attached 
 ossia.
 
            - Enter the number of the Source Staff and Source 
 Measure. The Source Staff is the scratch staff, and the Source 
 Measure is the measure in which you entered the music. (If you don’t know 
 a staff’s number, click the Staff tool and select the staff’s handle. 
 Select Staff > Staff Usage. The Staff Number appears in the 
 resultant dialog box.) If you want to specify a clef other than the default 
 treble clef, click the Clef Select button; to set a key or time signature, 
 click Key Signature or Time Signature. You can change the ending barline, 
 too, by clicking one of the barline types.
 
            - Specify the reduction value by entering a number 
 in the Scale To box. Generally, 50% to 85% (of full size) looks 
 good. If there are elements of the scratch staff you don’t want to include 
 in the floating measure, deselect the appropriate boxes in the Items to 
 Display section. You can also specify various positioning aspects of the 
 floating measure, such as the Top or Left Margin; for full descriptions 
 of these elements, see Ossia 
 Measure Designer dialog box.
 
            - Click OK (or press ENTER). 
 The (Page or Measure Assignment) box appears. If you wish, specify horizontal 
 and vertical coordinates for the measure (in the currently-selected measurement 
 units). If you’re entering a page-attached ossia, you can also specify 
 the barline-to-barline width of the floating measure.
 
            - Click OK (or press ENTER). 
 You return to the document, where the floating measure is in place. If 
 you’re in Page View, you can drag the measure’s handle immediately to 
 position the measure. In Scroll View, you have to click the “real” measure 
 to which you attached it; a handle appears, allowing you to drag the measure 
 into position.