Sometimes, a color (or range of colors) will be very present in your image. These colors can be used to quickly create an accurate Layer Mask. Even if the color cannot be used to select the object entirely, you can always harness the Brush tool to clean up stray areas.
1. Open an image with an area of continuous color you’d like to select.
2. Turn the Background layer into a floating layer by double-clicking its name in the Layers panel.
3. Choose Select > Color Range to make a selection based on a range of colors. Check the Localized Color Clusters option to reduce the selection area to just the chosen colors.
4. With the Eyedropper, click within the yellow area of the flower to make an initial selection. Hold down the Shift key and drag through other areas of the flower to add to the selection.
5. Leave the Fuzziness set to a low value (30-40). When most of the flower is selected, click OK to create an active selection.
6. Click the Add layer mask button for the layer. The petals will show well, but parts of the flower will be missing.
7. Add a solid color layer to make it easier to see your edges. Choose Layer > New Fill Layer > Solid Color. A purple layer will help things stand out nicely. Click OK and drag the solid layer below the masked flower.
8. Examine the masked layer closely. You will need to paint in part of the center of the flower. Additionally, some of the petals contain unwanted transparency. You may also have some leaves or stems that bled through. We can fix all of these problems quickly using the Brush tool.
9. Press D to load the default colors of black and white.
10. Select the Layer Mask attached to the layer.
11. Press B to activate the Brush tool. Adjust the size of the brush and its hardness settings so you have a smaller brush with a gentle edge (an 80-pixel brush with a hardness of 75% is a good place to start).
12. Paint in spotted or missing areas with white. You can remove any unwanted areas by painting with black.
13. When finished, you can save the image as a layered file such as a TIFF or PSD formatted file.