Plugins are deployed to TeamCity by placing the packaged plugin into the $<TeamCity Data Directory>/plugins directory and restarting TeamCity. You can also accomplish this via the TeamCity UI via Administration | Plugins List | Upload Plugin Zip and choosing the zip-file from your file-system. You will need to restart TeamCity (tomcat) for the plugin to take effect.
Download the latest version of the plugin from the JetBrains Marketplace.
Remove older versions
If you have an older version of the plug-in, be sure to remove it before upgrading to a newer one