Installing DKIM, SPF and DMARC records
You only need to do this if you have your own domain. e.g. xrnottingham.org
Setting this up helps improve the delivery rates to inboxes (rather than going to junk/spam).
This is highly recommended for lists over 5000 in size.
The extinctionrebellion.uk domain has already been set up. So if you use an email address on this domain as your reply-to email, then you don't need to do anything.
More info on how to get and use @extinctionrebellion email addresses here.
It is not possible to set up DKIM/SPF/DMARC for gmail/hotmail/aol/outlook etc. These should already be recognised domains.