On to the 4th!
I've followed the following two YouTube tutorials:
#16    • #16  3 x 3 square tiling  How to dr...  
#7    • #7 Alcázar, Seville  How to draw Isl...  
I used fineliner pens, a felt tip pen and colouring pens all worked well on the smooth 170 gsm thicker paper with nothing going through to the other side of the page.
I will continue filling the notebook with patterns, trying different materials so you can see how they work! Let me know if there’s anything you’d like me to try!
I'll follow my own tutorials, predominantly from:    / samiramian  
If you want your very own square geometry notebook, pre order from £10 for UK geometers from https://www.samiramian.uk/merch
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