To mirror operations, access Editor and:
1. Click on the Mirror button;
2. Click on the face of the piece you want to mirror;
The operations are mirrored:
To mirror specific operations, enable the tool and click and drag the mouse to select the operation. Select the edge of the face that will serve as a reference;
TIP: If you make a mistake in the register of operations you can undo it using the Undo tool. The same can be used successively until the desired point. If you have undone something and regretted, then click on the Redo tool.