How to create a simple button.
Step 1
Choose Insert and then click the New Symbol

Step 2
Select the Button from the symbol properties

Up mean the button is release, Over mean mouse over the button, Down mean click the mouse, Hit defining the area that will respond to the mouse click. This area is invisible in the movie

Step 3
Draw a rectangle to stage, then Click the second frame, labeled Over and choose Insert Keyframe

Step 4
Change the color of rectangle.
Step 5
Click the third frame, labeled Down and choose Insert Keyframe

Step 6
Resize the rectangle

Step 7
Click the labeled Hit frame, and choose Insert Keyframe

Step 8
Change the color of button
Step 9
Go to scene 1 by click the Scene 1

Step 10
Choose Window and then click the Library to show the Library Panel. The button have store in the library.

Step 11
Drag it to the stage, but it is unable to work like button. So, we choose Control and then click the Enable Simple Buttons

Step 12
Move over the button and click it to see the button work.
Up Over Down