Sit up straight with your back straight and shoulders back. Make sure your body weight is properly distributed on both hips. Bend your knees 90 degrees, maintaining the height of your knees equal with the height of your hips. To keep your knees and hips straight, place your feet flat on the floor or on a footrest if necessary. Pull your stomach in and lift your chest. This improves blood flow to your abdomen. The best way to achieve good posture is by practicing proper body alignment while sitting. Try not to slump from your tailbone to your head or bend your elbows more than 90 degrees. These actions cause poor spinal alignment that can lead to pain elsewhere in your body. When you sit up straight, you are giving your spine support which helps it remain healthy. When you sit for long periods of time, such as when you work at a computer, you need to change positions occasionally. Stand up every hour or so to relieve stress factors in your body, such as pressure points. Take five minute breaks every 60 minutes to walk around to maintain muscle tone and energy levels. Good posture makes you look and feel better about yourself. It gives you a feeling of confidence that shows in your demeanor. Good posture also benefits those around you, since you are less likely to suffer from workplace injuries when you are in good shape physically. If you want to improve your posture, start by sitting up straight in a chair.