My organisation are moving over to CiviCRM. We currently offer a range of different newsletters about different themes and issues. I will obviously need a group for each theme, and I want to build a profile that allows users to opt into the different groups based on their preferences.
However, I can only work out how to add a user to a single group when they fill in a profile, but I don't want them to have to enter their details multiple times, and I want them to be able to change their preferences later (I think via the GDPR plugin). Has anyone done similar? How did you manage this?
My approach now would be to have custom fields for each theme/issue that they select, and these are pulled into smart groups. But I'm not sure how a user could later manage their own preferences.