Enter a name for this symbol (i.e. My Button) and choose "Button" as behavior and hit OK.
3 There are 4 states as you would notice below (Up, Over, Down, Hit)
Up State Whenever the button is inactive
Over State Whenever the mouse is over the button
Down State Whenever the button is clicked
Hit State Defines the area of the button
4 Make Frame 1 (Up state) the current frame. Draw a circle using the Oval Tool (see image below). Center the circle using the keyboard arrow keys or your mouse.
Add keyframe at Frame 2 (Over State) and Frame 3 (Down State). To do this, right-click your mouse at Frame 2, then choose "Insert Keyframe". Do the same at Frame 3.
5 Add a new layer (Insert>Layer)
On your new layer (Layer 2), add blank keyframes at Frame 2 (Over State) and Frame 3(Down State)
6 While at Layer 2, go to Frame 2 (Over state) and draw a larger circle over the button (as shown below).
7 Again, while at Layer 2, go to Frame 3 (Down state) and enter 2 larger circles as shown below.
8 Add keyframe at Frame 4 (Hit state), to do this... right-click your mouse at Frame 4 (Hit state) and choose "Insert Keyframe".
Set Line Color = None and Fill Color = Black (or any color since Hit state will not show up in your movie)
9 Now, draw a square covering the whole button as shown in the image below.
Go back to your main movie by clicking on the "Scene 1" icon.
View your library (Window>Library) and your new button should be inside your library. Drag this button into your main movie. View your movie [CTRL+Enter] and check your button! You can also enable your button by going to Control Menu and choose Enable Buttons.