Eat smaller, more frequent meals during the day. Try to avoid eating within 3 hours of bedtime. Let out your belt a notch or two and wear looser, more comfortable clothing. Avoid girdles and other tight garments. The extra pressure on your abdomen forces acid upward.
Exercise is good, but avoid sit-ups and leg lifts which can worsen acid reflux.
Put gravity on your side. Sleep with the head of your bed raised. Use over the counter antacids if needed. Tums and Gaviscon are often helpful. But if you need this medications more than three times a week, see your doctor.