Step 1

Create a new document.

Width: 440 Pixels
Height: 100 Pixels
Contents: White

Step 2

Reset your colours. Then use the Difference Clouds filter several times until it looks something like this below.

Step 3

Use the Plastic Wrap filter with following settings:

Highlight Strength: 20
Detail: 15
Smoothness: 15

and you should get something along the lines of what we have below.

Step 4

Now bring up the Hue/Saturation box and use the next settings:

Hue: 200
Saturation: 60
Lightness: 0
Colorize Box: Checked

Feel free to play around the settings to get the color you like. This is what I got below using those settings.

Final Product

Congratulations! You've made plasma goo!

Below is a few other final products.

Above I duplicated the layer and flipped it horizontally then changed its blend mode to Lighten.