It really depends, my parents drove me to uni so I filled the car full of my stuff! Bedding, pillows, lamp, bathroom draws, cleaning stuff, toiletries, hair products, all kitchen stuff, photos, a few little ornaments plus clothes, shoes and lots of hangers and we also did a big food shop before we went there to save time once I was there with all my new flatmates!
Obviously you don't need all those things, I decided to take bathroom draws as I had an en-suite with nowhere to put things in and already had the draws which fitted in perfectly, if you can't visit your halls try and find some photos online or even email to see whats included, some university offer bedding or kitchen packs to buy from them before you go to save people especially foreign students bringing them or desperately shopping for them on day 1.
My friend had to get the train to uni so she decided she would just go shopping when she got there for kitchen things, all cleaning stuff, food, hangers, toiletries etc so only took bedding and clothes in one big suitcase with her.
Also worth thinking about how often your going home, if its fairly often you can leave a lot of clothes at home and swap whenever you go and even if its not till Christmas remember first term is all Autumn/winter so although we may get a few sunny days in September its not worth taking every pair of shorts and sandals you own.