PREPARE YOUR OWN FOOD WHEREVER POSSIBLE

are still not ideal low-carb fare. There are many recipes for quick and easy meals that you can prepare yourself at home. Try to do this as often as possible and turn it into a habit.
If you cook your own foods, you know exactly what contents you are adding in and you will be able to keep a watchful eye over hidden sugar and otherwise processed foods.
Another benefit is the cost savings over the long run. Even if you must go to the grocery store more often, you will save a significant amount per meal as opposed to eating at restaurants and fast food establishments.
It will also be easier to maintain your diet with your own favorite fresh food selections on hand.