The default color for guides and slices in Photoshop is light blue. When you are working on an image that contains the color blue or if you just don’t like the default color, you can change the color of these helpful guides, grids, and slices to a more suitable color using the Guides, Grid & Slices preferences dialog box.
1. If you are a Macintosh user, go to the Photoshop menu and select Preferences -> Guides, Grid & Slices to bring up this dialog box. As a Windows user, select Edit -> Preferences and select Guides, Grid & Slices. If you are in the dialog box from the previous task, select Guides, Grid & Slices from the dropdown menu at the top of the dialog box.
2. To change the color of the guides, select from a predetermined list of colors in the drop-down menu or select Custom to pick your own color. If you select Custom, Photoshop’s color picker pops up. Select the color you want and then press OK. The default guide color is light blue.
3. You can choose among two styles for guides: Lines (default) and Dashed Lines.
4. To change the color settings of the grid, you can select a color to your liking from a pre-determined list of colors in the drop-down menu or pick your own color by selecting Custom. If you select Custom, you’ll get Photoshop’s color picker, which enables you to select the color you want. Press OK when finished.
5. You can choose from three styles for the lines: Lines (default), Dashed Lines, and Dots.
6. If you want, you can change the intervals of the gridline. A gridline can be placed at any number of units per pixels, inches, cm (centimeters), mm (millimeters), points, picas, or percent.You can also select the number of subdivision lines that occur in between each gridline.
7. You can change the line color for slices, but only to a set of nine colors. The default color is, once again, light blue.
8. When you create slices with the Slice tool, they are automatically numbered starting with the first slice at the top left corner of the image. If you select Show Slice Numbers under Slices you can make those numbers visible.