Advice pages from Oxford's Department of Education can be found here. This document is intended to summarise suggestions and resources for people to move face-to-face teaching to an online format.

Higher Education e-learning sessions are available here (useful for spotting students at risk). 

Also recommended:

Miller, Michelle D. 2014. Minds Online: Teaching Effectively with Technology. Cambridge, MA: Harvard University Press. 

Baran, Evrim, Ana Paula Correia, and Ann Thompson. 2011. "Transforming Online Teaching Practice: Critical Analysis of the Literature on the Roles and Competencies of Online Teachers." Distance Education 32 (3): 421-39. https://doi.org/10.1080/01587919.2011.610293.

Both of the above are currently available through SOLO.

The following (free) online courses are also recommended: 

The University of South Wales, 'Learning to Teach Online', on Coursera. https://www.coursera.org/learn/teach-online#faq

Open University on 'Taking your teaching online'

https://www.open.edu/openlearn/ocw/mod/oucontent/view.php?id=77528