One of the best ways to avoid indigestion is to simply chew your food well before swallowing.
Coincidentally one of the best ways to help with indigestion is to pretend to chew food. Even though there is nothing in your mouth, the chewing sensation sends your body signals that help it to deal with what is going on in the gut. Five, ten, or fifteen minutes of chewing can completely eliminate a belly ache sometimes.
Another thing important to good digestion is fiber and starch. Whole foods with plenty of fiber and starch help the good bacteria in your gut to not only survive but to thrive. Potatoes are one of the things that provides this very good type of complex starch. Good bacteria help your body assimilate the nutrients that are needed from the food that you eat. They also help to break down and digest your food.
Indigestion can be caused by anything that contributes to the growth of bad bacteria, or the death of good bacteria. For instance chlorinated water can destroy the beneficial bacteria that live in the human gut. Avoiding chlorinated water will benefit digestion.
Processed foods tend to cause the same problem, because they interfere with and clog up the digestive systems.
Processed sugars tend to cause an overgrowth of negative bacteria in the gut, thus crowding out the good guys.
Additives such as carrageenan can also cause digestive problems. Carrageenan apparently makes the gut more permeable, allowing things to get through the lining that should never get that far. This causes digestive problems and allergic reactions.