In this tutorial you are going to learn how to make somthing a bit like this:
1.ok first make a new document in fireworks and draw a circle with #00FFFF as the color and 135 by 135 as the dimensions give it a gaussian blur.It should look a bit like this.
2.draw another circle the sameas the first exept make the line color transparent. set the fill type to gradient then linear then make the colors as shown in the screenshot below and position it so its behind the first circle you did.

3. draw another circle near the top left of the gradient circle but within the first circle and make it white with dimensions 22 X 22 then give it a gsussian blur like below.
And voila! you have a bubble!!

I hope you found this tutorial useful if you had any problems or would like to request another tute please Email me!