Hi. 7*7 is okay I guess. You can try with this, though I really forgot the actual size of these motifs,but I guess it's nearly similar to yours, it's actually depends on the yarn thickness and yarn tension too. So don't worry, and keep making 🙂 Hopefully this tutorial will be helpful. Sorry for late reply.
No need to make any basic chains, Make the squares first, join them according to your desired size. Check the tutorial for more information. Thank you.