Start With a Basic Shape
Draw a basic shape, such as a rectangle, using a basic fill style. Open the Style Inspector – Expert pane and use the action menu (looks like a gear) to Clone Style.
Add a “Hatch” Fill Style Component
Note that in this example the units of measurement are shown in millimeters. The units of measurement are set in the Drawing Setup, and displayed based on your settings in View > Display Units (points, drawing units, or map units) in the main menu.
Change Hatch Settings for Repeating Dot Pattern
Adjusting the “Density” setting will automatically generate a dot pattern. Changing “Line width” with a dot pattern will adjust the dot diameter. Changing the “Angle” will adjust the orientation of the pattern.
The density of the pattern is controlled by the “Density” setting. Alternatively, this can be fine-tuned by changing the “Spacing” setting to adjust the pattern spacing in one direction along a line. Then adjust the other direction by changing the “Dash” settings. Choose “Other” from the Dash setting and adjust the spacing of the dash pattern.
Name and Save Your Pattern to the Symbol Library
If you would like to save your new style for future use, name your new style and add it to the Library. When you click “Add Style To Library” you will be presented with the option to assign it to an appropriate category(s), such as “My Styles & Symbols.”