Look for a place to rent and how much deposit they require. My advice is not to use an agent as they take fees.
Also put yourself on the housing list for a permanent home with reasonable rent.
In the NW you can rent for anything from £90 - £150 a week and get something for just yourself, while you wait on the housing list.
When I moved out I winged it, but these were the days you could look in the paper, find a room, then walk the main street and come home with five jobs, which I did.
Now they want you to go and complete an engineering degree then do a five hour application form online to work the tills on Primark. It's got so difficult, it's a shame.
Basically though you want to find a place to rent, and rent it, then budget like mad on your food and social life and always pay your bills first! Then see what's left. You can eat for very little as a single person, very, very little. You just need to cook.