==============USING PHP ================
#using php header('Cache-control: max-age='.(60*60*24*365) .', public , must-revalidate');
session_cache_limiter('none');
// http://stackoverflow.com/a/1385982/2377343
									$year=60*60*24*365;//year
//Caching with "CACHE CONTROL"
	header('Cache-control: max-age='.$year .', public');
//Caching with "EXPIRES"
	//no need of EXPIRES when CACHE-CONTROL enabled
	//header('Expires: '.gmdate(DATE_RFC1123,time()+$year));
//To get best cacheability, send Last-Modified header and ...
	header('Last-Modified: '.gmdate(DATE_RFC1123,filemtime(__file__)));  //i.e.  1467220550 [it's 30 june,2016]
//reply using: status 304 (with empty body) if browser sends If-Modified-Since header.... This is cheating a bit (doesn't verify the date), but remove if you dont want to be cached forever:
// if (isset($_SERVER['HTTP_IF_MODIFIED_SINCE'])) {  header('HTTP/1.1 304 Not Modified');   die();	}




in Wordpress
==============================
//Set or replace $regex_path_match accordingly
  if (preg_match($regex_path_match, $_SERVER['REQUEST_URI'])) {
    add_action( 'send_headers', 'add_header_nocache' );
  }
  function add_header_nocache() {
    header( 'Cache-Control: ............' );
  }