To Display a Grid and Set the Grid Spacing

1. Click Tools > Drafting Settings menu.
2. In the Drafting Settings dialog box, Snap and Grid tab, click Grid On.
3. Under Snap Type, make sure Grid Snap and Rectangular Snap are selected.
4. In the Grid X Spacing box, enter the horizontal grid spacing in units.
5. To use the same vertical grid spacing, press Enter. Otherwise, enter a new value for Grid Y Spacing.

Note: The grid can be turned on and off with several other controls, including the F7 key and the Grid Display button on the status bar ( Find).