title: How to Integrate paypal SDK to my custom php website?
body: <p>I am developing a php website which needs to accept payments through paypal and credit cards.
  I have downloaded paypal php sdk from : <a href="https://github.com/paypal/rest-api-sdk-php" rel="nofollow">https://github.com/paypal/rest-api-sdk-php</a> .I want to implement paypal API to my website , But paypal have too many options to recive payments like , buttons , link flow etc . i need to make payment though curl functions with php. the sdk has examples but it confusing me. i got paypal api username, api password and signature from my paypal account. How to integrate this php paypal sdk to my custom website project ?</p>