The more fluid you drink during your meal, the more volume is placed in your stomach. This causes more distension in the stomach and adds pressure to the lower sphincter of the esophagus, creating the perfect condition for acid reflux. Try drinking between meals and drink water in small sips rather than big gulps.
Never, ever, EVER lie down after you eat! Even if you have only had a few bites, you may find that food comes back to haunt you in short order if you lie down. Eat all meals at least two hours before lying down for a nap or overnight to ensure that acid doesn't sneak back up your esophagus.
While vinegar tastes great on salads or french fries, anyone with acid reflux should avoid eating it. Vinegar, along with citrus fruit and tomatoes, is high in acid, and the more acid you eat, the more acid will return up your esophagus and cause you pain and discomfort after meals.
If you find you have heartburn more than once a week, you may actually have GERD. This is a serious condition which needs to be both treated and monitored by a medical professional. Talk to your doctor about your condition and whether there is a treatment out there to cure it for you.