Not that difficult. The majority of these accounts just sit there and and earn delegation rewards. The curation accounts follow either known curation trails or in the case of this account a mix of trusted users plus a curation account with random checks to make sure the upvotes are warranted.
Some of the accounts will get template posts which I will update on a regular basis, like the cro.gld account getting a weekly update with little commentary about how much I'm adding each week.
Once going though I'll just go through each account once a month (Hive Keychain is awesome), check returns, compile information and then distribute to the main account to support the community.
That's great, well done