When I came to the States for good, I was so confused by styles and what was in and what was out. I still didn't understand that clothing was made in sizes and I probably had a size I ought to be looking for, instead of just a style. I never got both right at the same time. So when I bought my first pair of shorts (a huge milestone for me, who grew up believing girls who wore shorts were slutty), I was thrilled that the waistline fit me perfectly, and didn't notice that they were old man shorts. I thought I was being so daring and cutting edge, fashion-wise, because my knobby knees were showing.
The first time I ever wore a real bathing suit, I was in my teens, and it was only allowed by my parents because I was helping at our home church's summer camp, and during the counselor/helper swim time I needed something other than a dress to swim in (for safety reasons, the rulebook said). So they got me a hand-me-down one piece bathing suit that was way to big for me. I would have been more modest if I'd just gone swimming naked, because that swim suit gaped in the crotch like you wouldn't believe, and the straps didn't stay up. But I didn't know that bathing suits were supposed to be skintight, so I had no idea that anything was wrong--I was so excited just to be wearing "normal" swim clothes like all the other girls. One camper asked me why on earth I was wearing a bathing suit that clearly didn't fit and was ugly besides, and it dawned on me that I wasn't like all the other girls after all. I was incredibly mortified.
Have you ever worn something that you thought was cool, only later found out was about twenty years out of date, or horribly ill-fitting?