When I started trying to reduce the amount of trash I made, I found that the biggest area of waste was in the kitchen. A takeout meal creates a lot of trash in the span of half an hour: non-recyclable styrofoam containers, disposable utensils and the plastic bag they're wrapped in, paper napkins, a plastic straw. For this and other reasons (health, pursestrings, convenience, yumminess), I bring my lunch to work daily.
Here's how to make it zero waste (it's sooo easy!):
Purchase a large reusable container.
Or rummage around in the back of your cabinets until you find one. I love this one, which is lightweight and durable - unlike glass, it won't break in your bag or if accidentally dropped. Mine has lasted me for years!
Bring your own cloth napkin (and utensils, if need be).
I wrap my utensils in my napkin and tie it in a knot (see photograph below) - the bundle is easier to keep track of and keeps my silverware clean until I'm ready to use it.
Overestimating how much food you'll need ensures that you won't need to resort to the vending machine at 3pm when hunger rears its head. I always add an extra piece of fruit, just in case: if I don't eat it, I can always bring it home or leave it on my desk for the next day.
Bring it back.
Once emptied, your lunch container can hold all of your food scraps from the day: apple cores, pistachio shells, banana peels, muffin crumbs. Stash these away so you can compost them when you get home.
These tips also work well for a road trip or plane ride. If I'm traveling somewhere, I'm almost never without a meal packed in this gear - plus, that way I have a fork, napkin, and reusable container handy, which helps me navigate unexpected situations while staying zero waste.