If keeping up with the ruler gets tough in your very busy and messy place then you should go for something large and conspicuous. Check out the Ruler Notebook! Printed on its cover are measurements in both cm and inches for your convenience.
The 5″x7″ notebook makes use of 100% recycled, natural white paper with soy based ink. Priced at $16.00, you could get one at baileydoesntbark’s shop at Etsy.