With just a few maneuvers you can put lines on a composite project and place moved objects precisely. First, we will go to the window that lets you set your preferences for the lines and the spaces between lines when setting up a grid.
>Edit >Preferences >Guides & Grid
Guides – You can set preferences for color and style. Click on the drop down menu to get the preset colors for the lines. The color you choose will then show up in the box to the right. If it is not exactly what you want, then click on the box. This will give you all the colors available. Once you click on a color inside this box and select OK, this will designate the color. Then the color box will now say custom. Style gives you two selections for the lines: Lines, Dashed lines. Click on the word for the type of line you prefer.
Grid – The color selection is the same as above for the Guides. I suggest picking a different color just in case you decide to use the grid lines and the guidelines on the same project. Style gives you three choices this time: Lines, Dashed, Dots. Over to the right you will set the distance between the lines. “Guideline every” put a number in the box, and in the drop down menu to the right you can select from: pixels, inches, cm, mm, points, picas, or percent. Select one and the lines will show up on the image even before you have closed out this window (if you don’t see these lines, look below for the instructions “To see it”). Make adjustments to how many lines you want. The Subdivision allows you to have lines that divide up the space selected. It makes it like the grid/graph paper we used in school that had dark lines and lighter lines. To find the center of your project use these settings: Guideline every 50 percent, Subdivision 1; this gives you an image divided into 4 equal parts.
To see it – You have to make sure there is a check mark in front of what you want to see: Rulers, Grid, Guides. On the Menu: >View , in the drop down menu. If there is NOT a check mark, then click on the word to put a check mark there, this will select the item. The inverse is also true. If you don’t want to see the grid anymore, click on the word and it will uncheck this to remove it from View.
Guidelines – If you have the ruler placed in the work space (>View >Ruler) then you have guidelines readily available. Click on the line that separates the ruler from the work space and drag it on to the image – simple as that. Once the line is pulled, you can see its placement in the ruler. The line is dotted until you let go of the click and drag. The dotted lines are in the ruler space (when your cursor is there) and the color is on the image. Now let’s say you know exactly where you want the line placed using mathematics. >View >New Guide will give you a window to input numbers and the guide will be placed on the image this way. Remove this line or lock it there with the options in this drop down menu for >View.