The royal popularized the delicate, ladylike print from her first public appearances. Diana in a white dress with black dots and matching hatCredit: GettyThe GistPrincess Diana had a flair for serotonin dressing that matched her buoyant and fashion-forward personality. Nowhere was that more evident than with her deep, abiding love for polka dots, which she wore throughout her time as a public figure. From the tiniest micro-print to big, bold spo…