To add a custom description to your form header, follow the steps below:
Navigate to the Header portion of the Header & Footer section of your form settings.
In the Form Header Description setting, add the information you want to display and use the toolbar to format it.
This includes the ability to add formatted text (markdown support), links, and images. If you wish to add images, simply select the picture icon on the far right of the description toolbar.
Optionally, you can set Form Header Description Type to Airtable field and choose an Airtable field under Form Header Description Field to have a dynamic description.
You can also choose to truncate the description, so long blocks of text need to expanded first. This can help decrease clutter while still providing useful information.