100 help please

I recently swam in my first meet and did not do as well as I want to do. I swam the 100 m in 1:23 but want to swim it in less than a minute. I am not sure what types of workouts I need to be doing in order to get my 100 time down. Any advice? I realize now that I need to focus more on my technique for one thing. In the race I panicked and just flailed my arms more than using technique. I can drastically improve there and right now I am planning on focusing on that. However, I don't know what drills would be good and what distances would be appropriate. Also, at what percentage of a race pace do I train? How often?