I'm about to enter my final year and I've survived solely on Student Finance, I wouldn't be able to afford to go to University otherwise.
My first year I lived in halls, it's important to note that due to my parents being a low income household I get the maximum student finance. I chose the expensive halls due to the fact I can't share bathrooms and wanted my own bathroom. I worked throughout the summer, so I had a good start up fund for Freshers. It was quite hard the first year, the halls were incredibly expensive. However, half way through the year I got a bursary from the University which helped a little.
My second year I lived off campus in rented accommodation. It was far easier, I had a far bit of money left over to spend on days out, clothes, etc.
I want to add, during the holidays I worked 40+ hours a week, so I always had some money stashed away. I also had an overdraft (my bank gave me a £1000 one with no interest) which sometimes I dipped into when I was expecting my next finance package.