27. Then press with the iron. The instructions say to use steam but I don’t – a dry iron is fine for a count of about 5 seconds. We’ll be stitching this down so we’re only looking for a temporary hold. Let it go completely cool before the next stage or it may come unstuck ! Once you’re underway, you can be sewing one piece together while the next piece is cooling. When it’s cool, trim off the excess backing strip, flush with the edge of the block.