This is the safest and most reliable method. We recommend our users use this method whenever possible. The unsafe visitor stays on the safe page where you paste this code.
You require PHP 5.4 or higher on your Linux web server (IIS is not supported). Please ask your hosting provider if you are not sure or not using our recommended setup.
Steps for PHP Paste Integration
STEP 1: Create your campaign from the dashboard.
Click here to read the complete article about how to create a campaign.
Get the code from the Integration screen
STEP 2: There are 4 methods of integration. Choose the first option PHP Paste method.
If you paste the PHP code in .html or .htm file or any other format, then code will not work. To resolve this rename your index.html file to index.php
IMPORTANT
Copy and paste the PHP code on top of your safe page, above everything else, strictly at the start of the index.php without leaving any white spaces.
Save the file and test your integration. Make sure your root folder where you uploaded the index.php file has proper permissions 755 or 775 or 777.
Test your integration
STEP 3: Paste your URL as mentioned in the image and click on the test button.
When you see Integration successful it means your cloaking is set up properly. It is ready to use now.
Sometime users with valid setup get errors. To fix that please remove the / from URL or type in complete URL inclucing index.php.
UPDATE
Please read this article to check if your cloaking is properly working or not.