The Adobe Illustrator CS3 tool called Rotate can be used to make the popular sunburst effect. The Rotate tool mathematically spaces and rotates the shape so there is no guesswork.
The Rotate tool is located in the Adobe Tool box and looks like an arrow made into a circle.
Create a triangle shape for the sun rays. This can be done by creating 3 points with the Pen tool, or by going to the star shape maker and pushing the down arrow to form a triangle.
Select the sunray and then click the Rotate tool. You will see an axis point in the middle of your shape. Click once to place the axis point at the bottom of the shape. The shapes will rotate around the axis point to form the sunburst effect.
Once the axis point is in place, hold down Alt + shift. This will duplicate the shape and rotate it around the axis.
To get the rest of the sunburst, all you have to do is click control (or apple) D, which is the shortcut for Duplicate. Repeat this shortcut until the sunburst shape has copied and rotated all the way around the axis point.
Now that you have your sunburst you can manipulate it however you choose. For instance, you can grab the white arrow and change the color of some rays or even go to the effect > filter gallery and put effects on the sunburst to make it pop.
Helpful shortcuts used in this tutorial:
Duplicate:(PC) Control + D(Mac) Apple + D
Copy and Rotate:(PC) Alt + Shift(Mac) Opt + Shift