The cloud looks aleady quite nice, however the bottom of the cloud is not looking natural. A real cumulus often has an extended base and you often find feathery detail. Since with one single cloud layer we have similar feel throughout the cloud(s). All we can do is decrease the amount of detail near the bottom by using a low setting on the Uniform parameter.

So what we will do (once you have found some nice parameter settings) is to save the cloud layer.
Save it as "Cumulus Tower"

Then load the cloud layer you just saved and we will modify it with the purpose of creating a cumulus base.

*Note:when you load a second cloud layer, its altitude is changed. In our case the altitude will be set to 2.3km, which of course is not useful if we want to create a cumulus base. So for now it`s ok to set the altitude of our new layer to 0.

Before we go back to the FE, change the name of the new layer to "Cumulus Base".

Now enter the FE. For the cumulus base we do not need 2 Gaussian Tooth nodes.

Connect the 1st Gaussian Tooth node directly to the Density output, then delete all the remaining unconnected nodes (now you should have a function that looks like the one we started with).
You can also delete the Offset node above the Gaussian Tooth node, because we can change the position by using the Metanode (Offset/Rotate/Scale).

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