I've seen some amazing handmade bookbinding tutorials on YouTube that basically walk you through everything from folding signatures to attaching covers. Honestly, the tactile feel of a stitched-together blank book is unbeatable for a gift. You could also go the digital route, which sounds weird but hear me out. Using something like Canva or even a simple PDF layout program, you can design the interior pages with quotes, inside jokes, or shared memories, then have it professionally printed and saddle-stitched at a local print shop. It ends up looking super legit. The key with either method is paper choice—a nice, thick paper stock makes all the difference between something that feels cheap and something that feels cherished.
For content, I once filled a small blank notebook with handwritten notes about why I valued my friend, one per page, and left the rest blank for her to continue. The binding was just simple Japanese stab binding with some decorative thread. It wasn't perfect, but the imperfections made it feel more personal. She cried when she opened it, which was the whole point.