Best way to setup your paypal. Same goes to setting up user paypal payment method.
  • Go to PayPal Developer Console and Login to your account after clicking the Log into Dashboard button
  • Go to REST API apps section and click the Create App button.
  • Add your own details for the new app and create it.
  • Switch to Live by clicking the button near your new App's Name.
  • Copy the Client ID and Secret
  • Navigate to "Admin / Plugins / Payments Addon" & edit paypal & input your copied Client and Secret keys.
  • Make sure to also switch the Mode to Live and Submit the new settings.