I don’t have an answer other than to include a link to the preferences page (and I just tracked down again that a link to https://meta.discourse.org/my/preferences will do the Right Thing) and a note to search for “activity summary” on the page.
Does anyone have a better idea?
Or maybe this should be in #feature. The feature request would be to include a link directly to the activity summary. Another might be to include usable id= tags on the use page so that you could link directly to the right spot on the page. (All I see is id=ember1234 tags, which don’t work across sites–are they stable on a single site?)