Glad you asked...
To write a fashion show script you need to use a lot of descriptive words. Make sure you describe the colors, textures, and hang of the clothes. Use fun and upbeat words.
Then again, this answer might help you...
Writing a fashion show script has to be done after all the clothing looks have been chosen. Once you have the line-up of the models and what they will be wearing, you can simply make opening statements describing the look the model is wearing and possibly the price or where it could be worn. Try to liven up the show with little personal opinions, and fun little tidbits of information about each look.

