Before we begin, we will have a look at the Swatch Palette. We need to set up our Global Colors right from the start. I picked four colors as a base. I chose a white, black and two grays. Once I added them in my Swatch Palette, I deleted all other color swatches.
Now let's set up the Global Colors. Double-click on the Color Swatch. In the Swatch Options Menu, select the option Global. Leave the Color Type at Process Color, then click OK. The Color Swatch now has a small white triangle in the bottom right corner. This indicates that the color is now a Global Color. If we apply a Global Color to any object or path, we can later change the color on the fly and it will be applied where the Global Color was added.
Create a rectangle with the Rectangle Tool (M). Use the size indicated in the image below.
