I started wearing costumes for Halloween. My mother and I would make them, after she found some pattern, or we would repurpose things in her closet. The first one I remember was a pumpkin. And in early type-casting, I was a doctor one year.
I didn’t do much during high school or college, but when I was in med school and residency we had some good costume parties. I made myself a blue Starfleet jumpsuit (more type-casting because of course I was Beverly Crusher!). And then I had the idea to get a group of us together to do a Starfleet costume set. This long before the term cosplay had come into use. We didn’t win the prize at the bar we were at, but we got lots of comments.
My best friend wanted to attend a Star Trek convention in San Francisco, and wanted to dress as one of the Duras sisters. We stared at the photos we could find to create some sort of a pattern plan, she found some vinyl, and we made the costume over a long weekend. We went to the convention and she was promptly put on stage with the other Klingons.
Since then, I’ve become more involved in events ranging from Renaissance to futuristic SciFi. Some costumes are more original and others recreations of costumes seen in books or movies (cosplay). Some involve extensive work and others are repurposing of existing items (including other costumes). There are more details in some of the blog posts.