Change your colour palette to white, select the brush tool and change the “master diameter” (brush size) to 30 px (also, I used a solid brush instead of the standard airbrush)

Draw a zigzag line from the top left corner to the bottom right corner similar to what is shown below.

Now select the smudge tool.

NOTE1: the smudge tool isn’t always visible in the tools selection. If you cant find it, search for the blur tool, click and hold and move your cursor to the smudge tool.

Change the brush size to 13 px and make sure the brush you chose is a circular airbrush.

Now smudge left and right across your document as shown below:

NOTE2: the best way to smudge in this would to be having a constant smudge and not letting go of the mouse button. However slower computers or computers which aren’t designed for graphics/gaming will have a lag time after you let go of the mouse button.

Do this until you have completely and thoroughly smudged the white line you created

Now, with the same brush, spiral clockwise (small spirals about 1.5cm max) over the entire document.

Now after you have finished, you should have something like this:

Now create a new layer on top of that and fill it with any bright or potent colour

Change the blending options to:

Colour burn:

Or overlay: