You have probably seen it in fantasy movies or games - a mage or a paladin with a massive grimoire or spellbook or whatever strapped to his side, which he would in times of need open and recite a chant/cast a spell.
I've been writing diaries since childhood, so several years ago I decided to make something GRAND, bought lots of writing paper and hacked together a thick notebook. Thick like 6-6.5cm thick, with 500-600 pages IIRC.
The question that's been tormenting me since then is 'how the hell do they write in these books?!' because obviously the closer to the bottom of the page the more your hand hangs in the air. The last few lines are written with basically no support for your wrist.
I've tried putting down something for support, but having another device the size of the book itself is not very convenient. For now I have to do it (depending on the mood) either in a way that resembles drawing with a brush (which is tiring, slow and sloppy) or supporting my right hand with my left (the pages are blank, so I have to put a lined sheet underneath the current page, and it requires the left hand to push the page down for the lines to be visible - therefore the second method doesn't work very well).
A quick Google search doesn't give any useful info, only advice about using writing mats, but I suspect they won't be very useful with a notebook this thick.
Before I dive into a futile endeavor of hacking together a miraculous wrist-supporting compact folding contraption, are there any alternatives you know of which I have missed? Some technique to hold your hand in a special way? Ways to put the book in a certain position to alleviate the problem?
The book itself is modifiable to an extent (meaning I can dismantle it and probably assemble back), so advice on reconfiguring the book itself is also acceptable.