How to Use the Live Paint Feature in Illustrator
Using the Live Paint feature in Adobe Creative Suite 5 (Adobe CS5) Illustrator, you can create the image you want and fill in regions with color. The Live Paint bucket automatically detects regions composed of independent intersecting paths and fills them accordingly. The paint within a given region remains live and flows automatically if any paths are moved.
If you want to give it a try, follow these steps to put together an example to experiment with:
Make the circle large enough to accommodate two or three inner circles.
As long as you aren’t on the Type tool, you revert to the default colors of a black stroke and a white fill.
Enter 75% in the Uniform Scale text box.
You see a smaller circle inside the original.
This duplicates the transformation and creates another circle inside the last one.
This activates the circles you just created.
The Fill swatch is at the bottom of the Tools panel.
Choose any fill color.
See how the different regions become highlighted?
Now try it with other fill colors in different regions.
A companion feature to the Live Paint Bucket is support for gap detection. With this feature in its arsenal, Illustrator automatically and dynamically detects and closes small to large gaps that may be part of the artwork. You can determine whether you want paint to flow across region gap boundaries by using the Gap Options dialog box, accessible by choosing Object→Live Paint→Gap Options.
Before you save a file for an older version of Illustrator that uses the Live Paint feature, first select the occurrences of Live Paint and choose Object→Expand. When the Expand dialog box appears, leave the options at their defaults and click OK. This setting breaks down the Live Paint objects to individual shapes, which older versions of Illustrator can understand.