The most important part of setting up Paypal for WebinarIgnition is to configure the auto-return url in Paypal.
This is the url to which your users will return to after making payment and is how WebinarIgnition will know that someone has paid for the webinar (and thus allow them to register).
You can find the return url in the "Thank You Page URL" field in the "Paid Webinar" section of the the Registration Page settings page. It will be of the following form: https://example.com/webinar-title/?DotnapyDCa2CDpVN7R8vjjkJssMG6Hxp
The information on how to specify this auto-return url in Paypal can be found here:
Once this is done, let WebinarIgnition know the url of the page where payment should be made (the Payment Checkout URL). Specify this in the Payment Checkout URL field in the "Paid Webinar" section of the the Registration Page settings page.
You can now set up Paypal payment in any of the ways that Paypal provides; these are specified here: https://www.paypal.com/merchantapps/appcenter/acceptpayments/checkout
Let's use the easiest, as an example, which is the first one on that page, "Quick setup for individual items". In this case, you would have to create your Paypal button then paste it on one of your wordpress pages (this will be the Payment Checkout URL I mentioned above).
NB: when pasting, use an "custom html" block.When someone clicks on this button, they would then be able to pay with paypal and would be redirected to your webinar registration page (i.e., the auto-return url you specified before) and would be able toregister.
To sum up: set up auto-return url in Paypal, specify Payment page (page containing Paypal button on your website), copy and paste Paypal button in Payment page.
And aside, I'd like to mention that these steps will work with any payment provider, as long as you can specify the checkout page (you could use woocommerce for this) and the auto-return url.
I know this can get a bit confusing at first, so please do not hesitate to let me know if you find any of this unclear or if you get stuck.
Thank you and best regards,