I think we all have the Blank Page Syndrome. We want it perfect. Well, we just aren't perfect creatures of Nature. Our book should be a reflection of ourselves. Therefore, any bloopers will be signs of character, tasks accomplished after strenuous effort, and lessons learned. Those antiqued, yellowed and torn-edged books got that way from use and activity. Spilled incense ash, tipped candles, pen blobs & inky finger prints provide testimony of their value. So get over it and get on with it
I've used copious quantities of White Out correction tape that comes in the press on spool applicator. When I wrote over it, I couldn't tell it was there. I have covered over whole paragraphs with a cut to fit piece of paper Glue-Sticked into place, and used craft boarder tape to hide the seams, and i once razor blade cut a page out that was really botched. I can't even find the gap now.
Big tip for drawing: use pencil then go over it in ink, and never double-stroke a line. It looks bad. White it Out then re-ink.
One thing I've found useful, and I've done assorted sized books, hand printing and illustrated with doodle-quality sketches, as well as cut&paste, has been to write text on the right-hand pages because that side lays flat, and draw or diagram on the left-hand page. Nothing moister than Glue Stick in moderation keeps pages from wrinkling and bleeding through, although ball point inks bleed after 10 or more years.
With smaller 4x6" books, I've written exclusively on the right hand page because it laid flat, and i went all the way through the book, then flipped the book upside down and went back the other way, continuing on. That let me write on both sides of the page, and when reading it the left side is upside down. And that's ok because it can only be read by flipping the book anyways. The few sketches were done within the text. Cut and paste will cause pages to spread if you use a lot of pics. Character!
To break the ice, plan the layout on a scratch pad of paper, plan to leave 2-3 blank pages per section for additions. In spell recording, leave a 1/2 page blank after each spell for follow up results comments and tweaking. The texts that don't change or aren't added to, like rules of conduct, magical laws, etc., can be put in front, leaving the recipes and spells, or the growing parts at the end for additions.The BOS is a working book, and record like lab notes. Cats will sleep on them, and occasionally chew corners just because they can.