Make a New Document

Make a new document, anysize doesn't matter. Now press "D" on your keyboard to reset the foreground and background colors to black and white. Make sure your background is WHITE.

Gradient Tool

Select the Gradient Tool. Make a whole bunch of gradient lines like below:

Now apply Filter>Stylize>Glowing Edges with these settings:

Then apply Filter>Artistic>Plastic Wrap with these settings:

Press CNTRL+U and apply some color: