Preview:

Underwater Explosion Design.

Step 1:

Let’s start out by creating a new file. I used a 600×600 pixels canvas set at 72dpi, and I filled my background with #000108 color shade. Now create a new layer set and name it ‘Jelly Fish’. Then grab the stock photo below and insert it into your canvas.

Step 2:

Duplicate the jelly fish image twice and set them up as shown below, use the transform settings such as resize, rotate etc through Edit to make each jelly fish unique.

Step 3:

Duplicate the ‘Jelly Fish’ layer set and merge it down through Layer > Merge Layer Set. Now apply a soft gaussian blur through Filter > Blur to the duplicated jelly fish layer and rotate it through Edit > Transform. Then set the layer’s blending mode to Hard Light

Step 4:

Add more unique jelly fish designs on your canvas.

Step 5:

Add a marquee selection around your canvas and copy merged it. Now paste and apply a soft gaussian blur through Filter > Blur. Then set the layer’s blending mode to Color Dodge.

Step 6:

Duplicate the blurred layer with a color dodged blending mode to make the effect thicker.

Results:

Underwater Explosion Design.