I do what butterpie does but the other way round. I get paid/all ingoings into one account and transfer all I need for bills into my other account.
Having online banking means I can manage all our accounts 24/7 and can transfer money between immediately - even just for 24 hours just to cover a direct debit. SO I don't tend to get any bank charges.
Also it means I can transfer the odd 5quid here and there into my savings and also ds account (or even less if I don't have that much) so even though we are on a low income I can (very slowly admittedly) try and build them up.
Pre chop onions/garlic/ginger/herbs etc into portion size amounts and freeze so that they don't go off and you can cook from scratch very easily and cheaply when tired. I also freeze stock (as icecubes - I boil it down so one ice cube = 1 stock cube so easier to store). Any fruit or veg you can freeze is a bonus as most can be used from frozen.
Also some things like peppers are cheaper to buy by the frozen bag than by fresh - as we only eat them cooked it doesn't make any difference so worth checking the prices of your frozen veg compared to fresh.
We also use supermarket for deals on large joints of meat - buy them up and chop them into 3 or 4 portions and freeze. Though unless good offers our butchers is cheaper.
Would love to get a chest freezer for the garage for more freezing as it saves so much money in the long run. Grated cheese/breadcrumbs/meat/fish/pastry etc all can be frozen adn stops anything going off (which was our main expense before).
We have a local farm shop that is pricy for meat and cupboard goods but so much cheaper than supermarket for fruit/veg (which they grow on site). Also if anything is going out of date they give it to you for free (and then I can prep and freeze it).
At the moment with both me and dh at home we can shop every couple of days which saves money for us as we only buy what we need when we need it. Otherwise we try to do a monthly shop (online) and then just use the farm shop/butcher weekly. As I've been ill though we are back to supermarket which actually costs more (though I always check the price down section).
Places like iceland/farm foods are brilliant for frozen veg adn for your basic frozen products. Often much cheaper than standard supermarkets.