It is possible, but also depends on where you're living (if its London that would be almost impossible) up North you could definitely do it. Last year I probably lived off around £80-£90. In terms of budgeting some tips I have, when I knew I was going to be really tight for money one week I would take my weekly budget money out of my bank and not take my cards out with me, when you have you're bank card its very easy to spend money as it doesn't feel like real money if you get what I mean. Also if you're self catered I used to make weekly meal plans that way you don't overbuy food and its less waste