Make a circle selection on a new layer, doesn't matter what the background layer is.
	Fill it with white
	Now using the eraser, choose a large soft edged brush and set the opacity down to around 30%, then delete the centre out like this
	Paint in a hightlight with the airbrush
	Apply the artistic/neon glow filter to it
	Make a selection just inside your bubble and on a new layer fill with the rainbow gradient
	Apply the distort/ocean ripple filter, i used s10 m5 but it doesn't matter much
	With the circle still selected apply the distort/wave filter, just keep pressing randomize until you get a nice oily effect
	Set the blending options to color burn and knock the opacity down to around 15%. Thats it.

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