convert 120v to 12v

My 120V light is controlled by a wall light switch inside the house. If I would repalce it with 12V LED light kit, how can I use the exinging light switch? Or can I? Ofcourse, I know I need a 12V transformer.

You can use the existing light switch once you add the transformer. You’ll simply turn the light off and on to change the colors and lights shows.