First Open A New Document. And Draw A Circle With Ellipse Tool.And Fill With Any Color.
Now Select Circle With Picktool Convert Shape Into Curves By Pressing Ctrl+Q.
Now Goto Tool Box And Select Roughen Brush Tool.
Now Follow The Settings For Roughen Brush Tool.
And Drag By Holding Mouse left Button On Edges Of the Circle.
Now You will Get The shape Like Below.
Now Change Angle to 45 Degrees And Drag On Edges Of The Circle.
Then You will get The Shape Like Below.
By Changing Angle You Can Get Different Types Of Roughen Edges To Your Shape.
Now Select Circle With Picktool Convert Shape Into Curves By Pressing Ctrl+Q.
Now Goto Tool Box And Select Roughen Brush Tool.
Now Follow The Settings For Roughen Brush Tool.
Now You will Get The shape Like Below.
Now Change Angle to 45 Degrees And Drag On Edges Of The Circle.
Then You will get The Shape Like Below.
By Changing Angle You Can Get Different Types Of Roughen Edges To Your Shape.