The front of the cushion consists of 16 rectangular blocks, each of which is knitted in two colours using the intasia method. The blocks are then sewn together using mattress stitch. (I assume you can also knit the whole front in one piece, but then you’d have to measure the results to get the back correct.) The back consists of four wide stripes, one in each colour.

Size: 62 cm long by 42.5 cm high. Each seamed square measures 15.5 cm long by 10.5 cm

Yarn:
one 100g ball each in
Moonstone (112)
Buttercup (132)
Satin (116)
Mallard (144)