I had to cut the pages at a printing shop because without a hydraulic guillotine, neatly cutting so much paper is just not possible. I've tried many methods but ended up with just uneven and ragged pages.
For binding, i chose the "perfect binding" technique with a softcover. It seems to be the easiest and least labour intensive. Binding the pages was actually easier than i thought.
I've designed the cover around a stunning artwork by Suzuka Youraku. Here is her pixiv page: https://www.pixiv.net/en/users/53055517
Full cover can be accessed here: https://drive.proton.me/urls/4ZWBW7ZHH8#vtkVwb3pFArN
In the end, I'm happy with the result. It cost me very little. In total the 400 pages book came at around maybe 5€ to make
(part 4 of my bookbinding project)