Once again, duplicate the layer Circle 07 now and rename the duplicated to Circle 08.

Erase the style and scale down the layer Circle 08 to 77%.

Enter the Layer Properties.

And here's the result, so far.

So, I know this is a kind of a boring thing to do, all the time but believe it or not that's the only way of reaching the realism in here.

Now, duplicate the layer Circle 08 and rename the duplicated to Circle 09.

Erase the style, decrease the opacity down to 10% and scale down the layer to 44%.