In order to manage items on the canvas, you must first highlight them. When an item is highlighted, it is considered in focus and any further actions taken by you will impact the highlighted item(s).
To highlight a single item on the canvas, follow these steps:
1) Switch to Select mode.
2) Click on an item. A highlighted item is surrounded by eight sizing squares and also a black border.
3) To un-highlight, click anywhere else on the canvas, and the node is deselected.
To select multiple items, follow these steps:
1) Switch to Select Mode.
2) Hold down the Ctrl key. This must remain held down for the duration of the multi-select actions.
3) Click on an item. A highlighted item is surrounded by eight sizing squares and also a black border.
4) Click on further items that you wish to select.
5) To un-highlight items, click on them again with the Ctrl key still held down.
Drag Select Mode
Another way to select more than one item at a time, is to use the Drag Select mode.
1) Click and drag across all the nodes/transitions you wish to select. When you do this, each of the nodes is surrounded by eight sizing squares and a black border.
2) Once you are happy that you have covered the area containing of all the items you wish to select, release the mouse button. The items are then be highlighted.
3) Switch back to Select Mode, and you can move the selected items around the canvas.