WebPlus X4: Send in the Clouds!

Hi Guys

I've had a request from one of my Customers to change the pale blue background of his Web Site into one that has Clouds!

Any ideas how I do this?

Is there anything available ready made in WPX4?

I just want to keep it simple with 'white fluffy type clouds'

I thought about taking a Photo and using that as a background but is there an easier way?