Your Grid Tool Kit
InDesign has a suite of tools that works together to help you set up and manage your grid.
Grid Preferences
Color: Personally I like to change the color of my baseline grid so that it's distinct from any custom guides I drawlight gray works well because it's not too distracting.
Figure 16.4. A seven-column grid allows more flexibility by offering a narrow "floating" column for additional material and white space.
Start & Relative to: This determines where the grid starts counting off from and whether that number is relative to the top margin or the top of the page. I prefer to start at 0, relative to the top margin. Relative to Margin will show only the baseline grid within the type area rather than across the whole page.
Increment every: This should be the same as your body text leading. Note this value will appear in your chosen unit of measurement, but these numbers are unwieldy if you're using millimeters or inches. Be sure to input this value in points.
Making your grid work will involve some rudimentary math, so it helps if you have an easy number to work with, like 12. You'll want to use this leading value (or multiples of it) for the spacing of the elements on your page. Make sure you are not using auto leading, which, depending on your point size, may give you leading values that are fractional. For example, if your body text is 11, your auto leading will be 13.2not a number you want to be juggling with.
View Threshold: Determines the view size at which the baseline grid becomes visible when you have Show Baseline Grid on. To view the baseline grid, choose View > Grids & Guides > Show Baseline Grid (Cmd+Option+'/ Crtl+Alt+'). You can selectively change the color and the view threshold of ruler guides by selecting the guides and choosing Layout > Ruler Guides.
Figure 16.5. Grid Preferences and Custom Ruler.
Figure 16.6. Ruler Guides.
Document Grid: Using a document grid turns your layout into graph paper. The size of each grid square is determined by the frequency of the horizontal and vertical gridlines and the number of subdivisions. If you don't want to subdivide the grid, make the number of subdivisions 1. Unlike grids created using a baseline grid or Create Guides, a document grid covers the entire pasteboard.
Grids in Back: When checked, the baseline grid and/or document grid (but not ruler guides) will be behind all other objects.
Custom Ruler: Set your vertical ruler to Custom width and use your grid increment as the amount. This will make the ticks on your ruler correspond to the lines of your grid.