2. Open the map with Photoshop.
3. Select the pen tool in the left toolbar to trace.
4. Draw a whole map as a picture.
5. After drawing all the maps, click the path on the right to enter the path interface.
6. Enter the path page, right-click the path layer and select the stroke path.
7. Enter the stroke path and select the brush tool, provided that the brush is set, and then click OK.
8. After tracking the path, press the shortcut key Ctrl+ ENTER to convert the path into a selection, and then press Ctrl+D to cancel the selection.