The first hurdle I encountered was that the instructions were in US terms, so I had to keep referring to a book of UK/US conversion stitches. This got a bit confusing as I kept getting them muddled up. It would have helped if I had printed off the pattern first, instead of reading from the computer - I could then have marked off each row as I finished it. If I had followed my own advice I wouldn't now find myself on row 13 with too many stitches! AAARGH!
Another thing - which I hadn't factored in - I should have checked my wool supply. If I intend completing the twelve months' squares and joining them into a blanket or throw, I need enough wool in my chosen colours to complete it.
Here is my first effort so far.
I am now off to try the filler square.