Create the operations for a single feature or the part that you want to pattern.
Add the operations to a new Browser folder by right-clicking and selecting Add to New Pattern from the pop-up context menu. Alternatively, from the Manufacture toolbar, select Setup > New Pattern to display the Pattern dialog.
Select Mirror pattern from the Pattern Type drop-down menu.
Click the Mirror Plane button and select the plane to mirror across from either the part or the Fusion Model Browser.
From the Operation Order drop-down menu, choose whether the pattern should re-order the operations according to tool or operation, or preserve the order of the operations within the pattern.