Within your sites ./system/expressionengine/third_party/ directory, delete the tag folder and upload the new one from the /system/expressionengine/third_party/ directory in your download package.
Within your sites ./themes/third_party/ directory, delete the tag folder and upload the new one from the /themes/third_party/ directory in your download package.
Go to the Modules area in the ExpressionEngine control panel and click the Run Module Updates button.