I know...I know... 2 posts in one day but I just wanted to share this with you before I forgot and packaged it up for it's new owner:
You can't beat a bit of garter stitch sometimes.
I used some random skeins of Debbie Bliss Rialto dk yarn which have been hanging about the stash for ages, in a semi-random manner interspersed with narrow stripes of cream. Each coloured stripe was 8 garter ridges (16 rows) and used approx 15g of yarn. I used 1 skein of cream for the blanket and another skein for a narrow (5 garter ridge) mitred border.
The ends were a bit of a pain but I consoled myself with a glass of wine and watching a back episode of the Great British Bake-Off.