I used a simple sunburst pattern for the inside of the granny squares in order to create a 'flower' effect but then finished it with double crochet on the outside.
The blanket came out relatively small - more like a lapghan than an afghan - because I only used 24 squares. I then added a multi-round border using double crochet for the blue and single crochet for the other colors in order to emphasize the blue a bit. I deliberately chose vibrant, loud colors because my 2.5 year old tends to be a bit on the quiet/shy side and I wanted a bit of contrast. I used Excel yarn and a 5mm hook.
Since this was my first granny afghan, I wanted to keep it small so that I could experiment. Some of the skills I learned in the making: how to randomize the colors, how to crochet the sunburst pattern, how to join grannies and how to complete a border. Though I really enjoyed the process of this, I will likely choose a more simpler color scheme next time and also try to more closely follow a pattern for the entire afghan (I am still not proficient in following patterns!)