To Edit a Cable Decoration
1. Select the cable with the decoration to edit.
2. Click Diagramming > .
3. Place the pointer over the decoration. The pointer changes to .
To select a different decoration symbol, right-click and choose Select cable decoration from the shortcut menu. Select a decoration symbol from the Select Cable Decoration dialog box and click OK.
To move a cable decoration, click and drag it to a new position.
4. Click to place the decoration.
* 
You cannot change geometry of cable decorations with shield portshapes.