The Kill la Kill: IF demo is now available for PlayStation 4 via the PlayStation Store in Japan, Europe (United Kingdom, France, Italy, Germany, Spain, etc.), Australia, New Zealand, and Southeast Asia (Hong Kong, etc.)
In the United States and Canada, the demo seems to only be available as a bonus for pre-ordering the game. However, if you have a PlayStation Network account for any of the aforementioned regions, you can download the demo without pre-ordering. Update 07/08/19 at 4:10 p.m.: The pre-order demo seems to be separate from the free demo. Queue up the free demo here: United States / Canada.
The demo includes four playable characters in Versus and Tutorial modes—Satsuki Kiryuin, Ryuko Matoi, Ira Gamagoori, and Uzu Sanageyama—as well as the first chapter of Story mode.
Kill la Kill: IF is due out for PlayStation 4, Switch, and PC on July 25 in Japan, and July 26 in North America and Europe.