Go to the releases page of this GitHub repository and download the latest release for your Mattermost server.
Upload this file in the Mattermost System Console > Plugins > Management page to install the plugin. To learn more about how to upload a plugin, see the documentation.
For a better cross timezone experience, enable Experimental timezone support. System Console -> Experimental Features -> Timezone = true
(Opt.) If your server is not configured for cross-team DMs (i.e. Enable users to open Direct Message channels with: is set to Users on same Team) then you will need to add remindbot to any team which wishes to use the plugin. This is done through the "Manage members" interface.