How to increase web site response time (IIS/Apache/NGINX)

IIS

IIS -> Expand Sites -> Select your site -> Click 'HTTP Response Headers' -> Under 'Actions' on the right hand side, Click 'Set Common Headers' -> Tick 'Expire Web Content checkbox' -> Select 'After' radio button and then set the Days value to 7.

Please try the below:

1. IIS -> Expand Sites -> Select your site -> Click 'HTTP Response Headers' -> Under 'Actions' on the right hand side, Click 'Set Common Headers' -> Tick 'Expire Web Content checkbox' -> Select 'After' radio button and then set the Days value to 7.
   https://technet.microsoft.com/en-us/library/cc770661(v=ws.10).aspx
2. IIS -> Expand Sites -> Select your site -> Click 'Compression' -> Tick 'Enable dynamic content compression' and 'Enable static content compression'.
   https://www.iis.net/configreference/system.webserver/httpcompression