Dear,

You can start your preparation by knowing the exact syllabus and good books.Speed is one factor that you need to keep up when you are appearing for any entrance exam. Work on your speed to solve questions faster and in given time.Practicing sample papers will enable you to know the type of questions asked in the exam, difficulty level and will also enhance your time management skill. Solving the sample papers will also help you know about the topics that have more weightage. You should be aware of the current happenings.Stay updated on the same, you can daily read newspaper. Also, go through fashion & design books/magazines. For the syllabus and books you can always refer:

https://design.careers360.com/articles/fddi-aist-exam-pattern

Hope this helps!