In order to prepare GK section of NIFT Exam, It is not necessary that you read each and every GK book. Awareness about current happenings is more important. For this, make reading newspapers a habit. Moreover, you should also know about the famous designers, who have contributed in this challenging field. Spend time on reading fashion & design books/magazines. 

You can also prefer Arihant books for GK & Do practise with the previous year papers as much you can with the given below link.

https://design.careers360.com/download/sample-papers/nift-sample-papers

Good Luck!