Did this a couple of times by the end of the game. You'll be wanting:
*pristine exhibits only
*all exhibits belonging to the same collection.
*expert matching the collection.
*exhibits need to be close together.
*all exhibits need buzz bonus active and maximum decorations.
*speakers giving a relevant buzz bonus
I did this with fossils. Completed fossils are all pristine and quite easy to find. Get yourself 6-8 Completed fossils. Should unlock by then.