Buy soap, ditch the shower gel and body wash products.
Buy a big set of microfiber cloths in the pound shop, ditch paper kitchen towels.
Automotive sections are good places to buy products like microfiber cloths, decreased, etc.
Look in your pound shop for cleaning products like loo cleaner. A little neat bleach will do the job too.
White vinegar for most cleaning jobs - look online for ideas on how and where to use it, and how to combine it with wash up liquid, etc for good results.
Own brand food items are often very nice.
Stop buying fresh fruit apart from apples, oranges, and bananas. Frozen fruit makes nice smoothies and you can bake with it. Freeze overripe bananas for baking.
Eat leftovers. Don't cook every day. Go meatless two days a week.
Look at your subscriptions. How many do you want to keep. I'd definitely keep union subs and it sounds as if your pet insurance is money well spent.
Look at your house insurance and shop around for better deals.
Look at the value you're getting out of your phone plan.