Permission required: Curate
You must pin a curated collection before you can add titles to it. You can pin up to 10 collections at a time.
To pin or unpin a collection, click the Curate tab in Marketplace, then click the pin icon next to the collection in the "Draft collections" list. When the collection is pinned, its pin icon will be filled in. When it's unpinned, its pin icon will be hollow.
You can also select a draft collection to open its details page, and then pin or unpin it from there.