Using Collections in the Bullet Journal is a great way to organize ongoing projects. Some longer-lived projects will spread throughout your book. Though indexing helps you keep track of where your collections occur within the book, it can be a hassle to keep referring to your Index, that’s where Threading comes in.
Let’s say you have a collection that lives on pages 2-6 then reappears on page 14-21, and then again on pages 45-62. To “thread” this collection, simply add the page number of the previous or next instance of that collection next to the current page number. That way, when you’re working on this collection, you don’t have to refer to Index anymore.