The Airtable Extension integration is an Airtable Block that is installed from the Airtable Marketplace. Once installed and set up it allows you to simply select a record then generate either a preview of the document or a live version of the document (without a branded footer).
Open the Apps panel
In the Apps panel, click "Add an app"
Confirm by clicking "Add app"
Once you've successfully connected to Documint you should see a list of your templates. Select the template that you would like to use for the active table. If you don't already have a template that you want to use with the active table then create a new template in Documint, return to Airtable and select the newly created template.
Once you've set up the app within Airtable you can start adding variables to your template.