Finally decided to get moving and created these pillows. I cut both horizontal and vertical lines from the main fabric but this was a bit complicated. I would recommend cutting one slice through your main square, adding a strip of contrasting fabric in the middle, then making a second slice through the whole block and adding a second strip of the contrasting fabric. I added a frame around the edge of the block using simple strips of a third contrasting fabric, because I think frames always finish so lovely. The back is navy and lime green as I was having trouble deciding, and is from another amazing little fabric shop, Spool of Thread owned by husband/wife amazing combo.
The back is an envelope closer- each piece is unattached but hemmed and overlaps by several inches.