This is the easiest way to start using Phenotero. Simply join the phenotypes and diseases groups. Note that you have to enable syncing within Zotero and you have to use the same Zotero-username. More information is available here
Once you have joined these groups, you will automatically be notified about updates in the database file, which can then be imported to your Zotero working environment with just one click (Zotero sync function). In case you have automatic syncing enabled in Zotero, this will start automatically.
Note that the syncing procedure may take a while. In our experience it should be less than one hour.