Read Omen. It'll give you something of a view of the heirarchy.
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It shows some Sith traditions that have been passed for five thousand years along a tribe of ancient Sith, so its undoubtedly not exact due to changes made over millenia, but I think its a decent portrait and I'm sure we'll see more as the FotJ continues.
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Perfection is a lifelong pursuit requiring sacrifice. The only way to get it quicker is to sacrifice the most.