GDPR - Best way to implement these EU privacy rules in Mautic?

Your software
My Mautic version is: Mautic 2.16.1
My PHP version is: 7,0

Your problem
My problem is:

I could not find any current solution to implement the GDPR rules in Mautic forms and custom fields.

Yosu Cadilla wrote a post about it but did not explain of how to implement it in Mautic

W-4 (a Swiss company) offers a commercial Mautic Mixin which is expensive

How do you solve it?

I think many Mautic users could benefit from your solution!

Thank you for your interest in solving this issue