Using Windows Explorer, locate the executable for `psql`. This file should be located in the `bin/` folder within the directory you specified when installing PostgreSQL. Copy the path to the file `psql.exe`.
Next, add this path to the PATH variable.
1. In the Control Panel, select **System > About** and click **Advanced system settings** (or search "edit the system environment variables" in the Windows Menu).
2. Click **Environment Variables**.
3. Under _System Variables_, double-click the Variable "Path" (or select and click **Edit**).
4. In the _Edit environment variable_ dialog box, click **New**.
5. Paste the path into the dialog box.
6. Click **Ok** and then **Ok** again.