Well a few off the top of my head:
Do you buy lunch everyday? If yes stop and make your own butties maybe just treat yourself once a week on a friday to something from the shop. You will find this saves lots.
Are you a smoker? Sorry but it does waste a lot of money just add up what you spend monthly and you will be shocked!
Do you club a lot? Why not try and get tipsy before you go out, this is a great money saver. Sometimes if i am not getting searched in a club i will even take a small bottle of spirits and just buy coke. (a lovely trick i learnt in my student days)
Are you a fan of Labels? Try cheaper brands they are just as good
Do you only buy labelled food? I have smart price stuff in my trolly everytime i shop, they taste as nice or even better sometimes
Well off back to work i go, hope this helps even a little