buy furniture/appliances/clothing second hand whenever possible, bonus points if you are handy enough to teach yourself how to fix something. this is how my partner got a new fridge.

only buy what is on sale at the grocery store - lose the notion that you have to stick to a strict list and build your pantry around what is most affordable at the time as this can often change. do not shop hungry, and do not try and stock up for weeks. shop sparingly and only when you need to - I go to the store every 3 days or so. this will keep you from over shopping.

learn to cook using the most minimal/basic ingredients - quality seasonings will go a long way and learning how to properly store left overs can feed you for weeks.