I think ordering a supermarket shop on-line and having it delivered, even with the delivery cost can be cheaper (there's always cheaper or free slots anyway). Stops frivolous spending.
I get my fruit and veg delivered from the local market. The amount you get is incredible and it makes you meal plan to ensure everything gets used.
Add beans to meals to bulk up, have a vegetarian dish once or twice a week.
Once a week we have a 'cheap' meal. Jacket spuds and cheesy beans, omelettes etc.
Sometimes, buying own brand or Aldi products can be false ecomony. We have found this with cereal for the DC, the absolute rock bottom price stuff tastes like cardboard and is wasted money.
Have to odd luxury to keep you on track, mine is ground coffee, just a strong cup, made first thing.
I have found having an amount going into 'locked in' savings makes me less likely to dip into a more flexible account. We've got one that is high interest but has to be held for at least a year. Minimum payment is £50, so not a really huge, massive amount iyswim?
Old bananas make lovely banana cake/bread.
If we do have leftovers, I mix into the dogs food (within reason, I draw the line at a madras!!), which bulks it up.
Unless I put something new on and think 'wow', I send it back/return it.