1) Keep spices away from sunlight and heat. This prevents nutrient breakdown and keeps them longer. I keep most in a drawer.
2) Get rid of the fancy gadgets you don't ever use, or give them to someone who could use it more often. Then just borrow it whenever you need it.
3) Keep fresh herbs like cilantro and parsley in a cup of water in the fridge, you can even cover them with a small plastic bag. This keeps them from wilting and losing nutrients. Change the water daily.
4) Store bananas separate from other fruits. Do not keep them in a fruit bowl with other fruits because the ethylene gas they emit causes other fruits to ripen faster (or rot). Which can come in handy if you need, say an avocado to ripen faster.
5) Store apples in the crisper drawer of your fridge. Apples and oranges are sensitive to ethylene.
6) The spottier the banana the more nutritious it is so if you can't stand the taste of them when they're browning, cut and freeze them (peel-less). Drop them in your smoothies later or make ice creammmm.
7) Green, red, and yellow peppers can be a pain to chop. So that you used them more often, chop a bunch of them up one day and store them in the freezer.
8) Meal prep is amazing, but easier for small families of say 3 people. I have a household of 5 and I might as well attempt to feed the football team 4 times a week in order to make enough ahead of time for my family. But if you can cook your meals in advance and store them for 5 days it is really helpful and keeps you from eating a bunch of junk.
9) Plug your sink when its empty, then throughout the day put your dishes in and when ready to wash them just fill with water and scrub away. This way you don't have to dig through the pile of dishes to get the the stopper.
10) Recycle ALL your paper, strips, tags, napkins, every bit of it. Not only are you creating less waste but your trash can will hold a lot more trash!
11) Invest in a crock-pot. You'd be surprised how many meals you can throw together and have ready and waiting for you so that you don't come home after work and have to cook every night. And keeps you from hitting the drive-thru or ordering take-out.