To apply color adjustments using the Polygonal Lasso:

1. Adjust the color settings on the left panel.

2. Click on the image to set the starting point.

3. Move the mouse to draw a first straight segment and click to set its end point.

4. Repeat to create additional segments.

5. Double-click to complete the polygon.

To apply different color adjustments to another part of the image, click on New Selection.