You only need this if all you want to do is make them change into an outfit they had picked.
The 2nd way of remembering is for if you want to write a special scene based on the outfit they picked (ex. blue dress, MC’s friend comments on her dress and says it’s blue like the sea)
Once a gain is gained, it will carry over so you can use it in your script many times. You could just go with the first way and later on in the party scene, you can use the if/elif/else to have someone compliment her on her dress.