Our first prom was 10 years ago! Both my girls did 2, Y11 and Y13.
DD1 has her own style and did not want a long fancy prom dress, she found her Y11 one online (did take a few orders and returns to get it correct). Did her own hair, make up and nails. Transport was dad's taxi as usual.
DD2 is more fashion conscious and her Y11 prom dress was bought in the spring during a family shopping trip to London. It was typical prom/bridesmaid style from Coast in the sale. It was a year of many weddings for us so was bought amongst other items not a special trip. Her hair was done by her regular hairdresser as we had thought to book her scheduled appointment for a cut and blow dry. Make up etc, all done herself.
Neither of my girls would have wanted to visit a prom dress shop and there were some very expensive horrors at the events, along with fake tan, fancy hair and make up.
They take after me, the only time I have had my hair and make up done for an event was for my own wedding and the only time I have had a professional fake tan was for my Brother's early spring wedding.