Laravel website - Payment Gateway integration

We have a laravel / PHP website. The client wants to integrate WS payment (an EU credit card payment company). WS payment sends us a full compressive step-by-step guide on how to create an integration of the Credit card payments + how to test it (first it should be test environment and after they check it should go to active - live). We need a pro PHP developer who is experienced with the integration of custom credit card payments systems.