After much swearing, stopping and starting I’ve finished the hat! I saw the pattern here about two years ago and have been trying to complete the hat since then. I have started it at least 5 times and had to call upon my wife’s expertise but it’s finally done! I actually started this hat in early September so it’s taken a couple of months of actual work. However, there has been a lot of practice before that.
The main problem I had with the pattern was size- I completed a chequered pattern hat to get practice at switching between colours using the intarsia technique but it barely fit our two year old!
I scaled the pattern up from starting at 90 stitches to starting at 120 stitches with the idea that it should fit either me, my seven year old nephew or our soon to be three year old. In the end it fits me quite comfortably! However, I will now be scaling it down slightly and intend to complete one for my nephew at some point…
I would recommend practicing basic technique first and, in particular, I found this video good for instruction on intarsia.
My version of this pattern can be downloaded here: R2-D2 Pattern.