I got my dress design off the internet and then made by a local dressmaker (this was unusual 11 years ago) but I really wanted to try on heaps of dresses. Nobody would come with me though, so the first time I got to try a dress on was my own one a fortnight or so before my wedding. Luckily it was the "wow this is the dress I want" moment though

As for the opening question, I would say a make-up and hair trial at a few different places to find the perfect one for the big day. Also some time visiting florists and bakers choosing flowers and cakes. All the fun stuff