Paste the code to you Carrd website’s HTML field.
Next, go to your Carrd website and find the HTML field. It is most likely in the form of an HTML/Code widget or module which you can find on Carrd’s dashboard. Add it to your page, and paste the code you’ve copied before to the HTML field. Save and update, and that’s it, you should have Common Ninja’s Messenger Chat widget on your Carrd website.