Where to start
Three roads lead to the same editor: choose New Food from the add button, tap Create food when a search comes up empty (the name you typed comes along), or scan a nutrition label and let it prefill everything.
The two steps
Details — pick an icon, name the food (that's the only required field here), and optionally add a brand. A barcode appears here too when the food came from a scan, and with one attached, future scans of the product find your food instantly. You can clear it on a food you're creating fresh, but the editor never scans or types one in: a barcode arrives with the food or not at all.
Serving & nutrition — first, what "one serving" means: an amount in grams, ounces, milliliters, or a countable serving. Switching between weight units converts automatically, and the gram equivalent stays visible so there's no ambiguity about what you defined.
Below it, an editable nutrition label. Calories, protein, carbs, and fat are the core; beyond them you can fill in fiber, sugars, fats broken down, sodium, cholesterol, vitamins, and minerals. Pick the label layout that matches the package in your hand — US-style, non-US-style, or the app's own order — so you can copy values line by line without translating formats in your head.
Save it, log it
From the editor you can log the food immediately or add it to the plate; either way it's saved and lives in My Foods, searchable like anything else. Custom foods are private — nobody else sees them unless you explicitly contribute them to the catalog.