I was worried that the corners might not sit flat so as I was going round the corner (If that makes sense) I did an extra chain between each single crochet. i am not sure if that is the correct way of doing things but it worked and I got it to on all four corners too!
The blanket is for a colleague at work who became a new Dad just before the school term ended for the Summer Holidays. I go back to work tomorrow and shall take in with me. I am really pleased with my first attempt, I used all of the blue wool, so I did not add to my stash and I have been using some of the white to practice other stitches. I have moved onto another project but it is a WIP at the moment so I shall say no more for now.