After Organization Gifts are enabled, you'll need to create or edit an existing online donation form and add the Organization Name element. Keep in mind that adding the data element is not necessary for offline donation forms.
For information on creating a donation form, see Creating Online Donation Forms.
Add the Organization Name Element to a Donation Form
The Organization Name data element can be found in the Donor Information section when editing the donation form screen. See To work with the donation form for more information.
Click here for the rest of the steps.