how to make this effect?

[Kalleheikki Kannisto]

That is a refraction effect. I don’t remember if you can do that in pure AE, but perhaps the glass effect does refraction.

The original image might be as simple as a couple of circles or a wiggled path, and the whole thing is put through a refraction effect — as if seen through a piece of mottled glass — at varying smoothness settings.

[John Cuevas]

I think a combination of fractal noise & find edges should get you most of the way there.

Johnny Cuevas, Editor
ThinkCK

“I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work.”
—THOMAS EDISON on inventing the light bulb.

[Chris Evans]

Draw some shapes, throw Turbulent Displace on it, increase the amount to around 1000, play with settings.