To Undo A Step:
- To undo one step, press CTRL+Z, or select the Undo button under Edit -> Undo.
- Repeat as necessary to undo as many steps as needed.
To Redo A Step:
- To redo a step you have undone, press CTRL+Y or select the Redo button under Edit -> Redo.
- Repeat as necessary to get back to where you want.

