I have not created a standard Buy Now button on PayPal for some time. One thing I noticed was a new feature called Smart Payment Buttons which I have started to look in to. For those who are a little confused with the process, please read on. At the end of this tutorial you should be able to create a Pay Now button for your own website.
Creating a Smart Payment Button
The first thing you need to do is head over to the Pay Pal developer website https://developer.paypal.com/home and login to the dashboard.
If you already have a PayPal business account you just need to login with your existing PayPal login details, You will be redirected back to the developer dashboard on the PayPal developer site.
In order to create smart payment buttons, you need to create create an app. Creating a new app will generate a client_id. The client_id is then used in the smart payment buttons code.
Please Note: If you create a smart payment button without logging in or creating an app, it will redirect the user to the PayPal sandbox after the user clicks the PayPal button.
Inside the developer account, select My Apps & Credentials, then select the live tab and click Create App
Enter a new App Name and click the Create App button