Simple answer: make your own food.
Most takeaway (like spike says) is flavored with salt because (a) it's cheap, (b) it masks other things if you're getting foods that are lower in fat, etc. because fat and sugar are also cheap flavorings and (c) it's used for preservation.
Get a salad, dressing on the side, or just get oil and vinegar for your dressing and you will avoid a lot of salt. There is still salt in growing plants -- you will never be 100% free of it, nor should you be, as it is a necessary nutrient -- but it's far better than standard takeout fare. Tomatoes and fish are often preserved with salt, and cheese of course is made with it.
Keep as well within 2400 mg/day as you can, and recognize that some days you'll be over, and that's healthy and as good as can be expected in our busy lives these days.