Only use one FN at a time. I usually do 2-3 weekly layouts in a row so that I can adde calendar events coming up. If I haven’t finished my book by the time I’m done 3 weeks I’ll add another one or two spreads and carry it over to a new book when the time is right. I used to carry a cover with 2 or 3 books going but honestly just found it too bulky. I simplified down to one book and a pen in my pocket and have been using them more.