- Open the Project Structure settings, and then click the Load Path page.
- In the Load Path page, click
. - Locate the desired path in the Select Path dialog box.
- Right-click the desired directory in the Project Tool Window.
- On the context menu, point to Mark Directory As node.
- Choose Load Path.

The directory in question is marked with the source root icon
.
To unmark a directory, choose on the context menu.
The directory is then denoted with regular folder icon
.

