©1996 Russell G. Taber -- All Rights Reserved

Show Info Palette from the Windows menu (Window>Palette>Show Info.)

Using the rectangular selection tool, select a 20 pixels square.
(Pressing the shift while making a selection will keep it square.)
Watch the Info Palette while doing this the see the selection size.
This sets the proportions of the grid.

Invert (cmd-I).

Holding down the Command and Option keys, press the down arrow key 4 times
(this sets how thick the horizontal lines will be.)

Holding down the Command and Option keys again, press the right arrow key 4 times
(this sets how thick the vertical lines will be. )

(Looks like this)

Edit>Define Pattern

Select All (Cmd-A)

Edit>Fill: Pattern, 100%, Normal.

Easy Grids!