Use the name of the account that uploaded the video as the author.
In-text citation
(American Psychological Association, 2017)
Reference List
American Psychological Association. (2017, July 26). Smoking cessation interventions with behavioral health
populations [Video]. YouTube. https://www.youtube.com/watch?v=tytUyjz74GQ
Format:
Author Surname, Initial(s). (Year, Month Day). Title of video [Video]. Site name. URL