First of all make sure that dynamic compression is enabled and configured in IIS.
Afterwards you just have to add the following section to your IIS config(located at %WinDir%\System32\inetsrv\config\applicationHost.config):
Afterwards you just have to add the following section to your IIS config(located at %WinDir%\System32\inetsrv\config\applicationHost.config):
Maybe it should work too if you add this to your web.config, but I couldn’t get this working.