How to Burp Loudly
There are few ways to help your burp loudly to beat your friends or just for your own amusement. Get a carbonated drink and drink it as quickly as you can to swallow more gas. If you don't have a drink, just swallow a few times to get more air in your stomach. Stand or sit straight with your shoulders back to make a straight path from your stomach to your mouth. Try tilting your head back a bit to make an even smoother pathway. Wait a few seconds, then open your mouth and burp by tensing your stomach muscles. You can also hold the burp for a few seconds to build up pressure. Just don't burp too much in a short period of time, since you can upset your stomach.
Choose a carbonated beverage. A freshly opened canned beverage will provide the most carbonation. To burp loudly you will want to drink the beverage as fast as possible. Choose something that you like, so you'll want to drink fast. Be careful that it's not too sweet, or it may upset your stomach. Pick a drink that is cold but not so cold that it hurts to drink quickly. Avoid drinks that have gone flat and have been open for a long time. Drink the beverage as fast as you can. The more carbonation you are able to take in, the larger the burp you can release will be. Take large back to back gulps of the drink, and try to finish it in one attempt. You don't need to take large mouthfuls, smaller sips will introduce more air as you swallow. Resist the urge to let out small burps as you drink. Wait for 3 seconds to let the drink settle. Make sure that all of the beverage is at the bottom of your stomach and the gas bubbles have had a chance to rise. Stand up or sit up straight. Make a straight pathway from your stomach to your mouth by extending your shoulders upward and stretching your back. You want to allow the gas travel as smoothly as possible from your stomach out in order to produce the loudest burp. Release the burp. Let the accumulated gas go all at once. The sound of your burp will reflect the amount of air you are releasing from your stomach. Open your mouth. Squeeze your stomach muscles similar to the feeling of vomiting. Let the air escape your stomach. Squeeze your abdominal muscles as you burp. Amplify your burp by pushing more air out faster. Use your abdominal and stomach muscles to squeeze your stomach to push out a larger volume of air. Imagine you have a large bite of food in your mouth. To swallow air, you need to go through the motions of swallowing without food. Think of the feeling of having a mouthful of food. Contract your throat like you are swallowing. Go through the motions of swallowing without food in your mouth. Each swallow will draw more air into your mouth. Pull the air in your mouth to the back of your throat. Swallow a gulp of air. Swallow several gulps of air. Repeat the process of swallowing air several times to build up a bubble in your stomach. The more air you are able to get into your stomach, the larger and louder your burp will be. Contract your stomach to combine the air bubbles. Squeeze your abdominal muscles to push all the air together in your stomach. Prepare for the upcoming burp by pushing all the air into one bubble. Hold the burp in for a moment to build up pressure. Open your mouth to release the burp. Give the air a way to escape your stomach by opening your mouth. An open mouth allows the air to resonate and creates a louder sound. Force the burp out of your stomach. Wretch your stomach and diaphragm muscles to squeeze the air out of your stomach and force the burp to emerge. Keep your throat and mouth open to allow as much air to escape as possible. A longer burp will generate louder sounds. Contract your diaphragm muscles towards the end of your burp to squeeze any remaining air out. Keep your mouth open during the burp so the sound is not muffled. 
Choose a carbonated beverage. Drink the beverage as fast as you can. Wait for 3 seconds to let the drink settle. Stand up or sit up straight. Release the burp. Squeeze your abdominal muscles as you burp. Imagine you have a large bite of food in your mouth. Contract your throat like you are swallowing. Swallow several gulps of air. Contract your stomach to combine the air bubbles. Open your mouth to release the burp. Force the burp out of your stomach. 