Question about Avatars installation

Hi,

I'm trying to install the Avatars plugin. I am on a Mac (no right click available). I'm fine up to the part where you have to create a new directory. Is this the same thing as a new folder?

Moving on, when it says to create new user directories inside the new Avatar directory, how many am I supposed to create? Does this mean when someone creates a new blog I have to manually create a new directory for them?

Also, is it really necessary to install Avatars before installing the Communities plugin?

Thanks!