Welcome evil, I would look at the big bills first.
Plan of action.
Ring phone provider and ask for a cheaper package. If they cant lower it ask how much to cancel it. They wont want you to cancel so hopefully that will push them.
Ditto for mobile.
Meal plan, do one big shop in aldi/lidl and aim for no top ups. No lunches out.
Is that electric bill weekly or monthly? can you find a cheaper deal on moneysavingexpert energy club? renting still means you can switch providers.
Look on the waterboards website, they often do free water saving devices. It might knock a few quid a quarter off but it all adds up.
Check if you are in credit with any utility suppliers.
Do you have a topcashback account or quidco? paying car insurance upfront is the way to do it cheaply. Especially if you've shopped around.