a cushion insert/stuffing
I have used a cushion from IKEA that costs 49p and measures 14in x 14in or 35cm x 35cm. However it is blue so be careful when wanting to use lighter fabrics.Firstly iron all your fabrics and trim your stitched square. I trimmed mine to 6in x 6in as it was only small. Obviously your sizes may vary.I cut 4 rectangles of 6in x 2 in and 4 squares of 2in x 2in for the first border.