How to Create Guides in Photoshop CS6
Guides are nonprintable horizontal and vertical lines that you can position anywhere you like within a Photoshop CS6 document window. Normally, they’re displayed as solid blue lines, but you can change guides to another color and/or to dashed lines.
To use guides, choose Edit→Preferences→Guides, Grid & Slices (or Photoshop→Preferences→Guides, Grid & Slices on the Mac).
Guides would be useful even if they were only, well, guides. However, they have another cool feature: Objects and tools dragged to within 8 screen pixels of a guide are magnetically attracted to the guide and snap to it. That makes it ridiculously easy to align objects precisely.
Because the objects snap to the guides, you can be confident that you’ve placed the objects exactly on the guide and not just near it. You can turn off the Snap to Guides feature if you want a little more control in your arrangements.
To place guides, follow these steps:
Make sure that rulers are visible in your image.
Choose View→Rulers to display them, if necessary.
Click in the horizontal ruler and drag down to create a new horizontal guide. Release the mouse button when the guide is in the location you want.
Anytime you create a guide by dragging from the ruler, the Show Guides option automatically switches on. At other times, you can show or hide guides by choosing View→Show→Guides or by pressing Ctrl+semicolon (Command+semicolon on the Mac).
Click in the vertical ruler and drag to the right to create a new vertical guide.
When you release the mouse button, your new guide stops.
You can also create a horizontal guide by Alt-clicking in the vertical ruler (Option-clicking on the Mac), or create a vertical guide by Alt-clicking in the horizontal ruler (Option-clicking on the Mac). Use whichever method is faster for you.
Finally, you can choose View→New Guide and enter your desired orientation and position.
Use the Move tool (press V to activate it) to reposition your guides.Credit: ©iStockphoto.com/Tanya F. Image #13538097