This is a sample tags script from criteo, the script should be implement on DFP

criteoTags.js

/* This script adding after tags DFP
 * googletag.defineSlot('/95250053/LIPUTAN6_LB_HEALTH', [[728, 90], [970, 90]], 'div-gpt-ad-1435336898160-0').addService(googletag.pubads());
*/

var crtg_split = (crtg_content || '').split(';');
var pubads = googletag.pubads();
for (var i=1;i<crtg_split.length;i++){
pubads.setTargeting("" + (crtg_split[i-1].split('='))[0] + "", "" + (crtg_split[i-1].split('='))[1] + "");
}

/* This script adding between script
* googletag.pubads().enableSingleRequest();
*/
 googletag.pubads().setTargeting('72890_Crt', ['1']);
 /* 
  * googletag.enableServices(); 
 */