Better posture can make you look both taller and thinner. When you hunch over or slouch, you immediately lose inches off of your height, which can also make you look heavier. By improving your posture, you can look taller without ever growing. It's a simple change you can make in your life to make you look better and feel better.
Look in the mirror and assess your posture. According to "Shape" magazine, when you turn to the side you should be able to draw an imaginary line from your earlobe to your hip, knee and ankle. If your line is wobbly, straighten up. Press your heels into the floor, raise your neck and rotate your shoulders backward until you're able to achieve a straight line. Chances are you look suddenly taller and leaner with little effort.
Swap your unsupportive flats and flip flops for more sensible footwear. Properly supported flats can help you stand taller by centering your weight properly. Even if you're a slave to high heels, look for those with supportive center arches, or insert orthopedic insoles to help you look even taller. If your job requires you to stand for long periods of time, place a rubber mat on the floor for better support, suggests the Spine Health website
Sit straight when you're in an office chair. When you stare at a computer all day long, you may be prone to hunching your back to see the monitor better. Adjust your monitor so you can see it from a proper sitting position and your spine will look lengthened and you'll seem taller, even when seated. If you have trouble maintaining ideal posture, slip a tennis ball between your back and the seat back, and hold the ball in place as you sit.
Relax your body. While it may sound counter-intuitive, maintaining rigid posture all day can cause back pain, which in turn can cause you to stoop your shoulders when you release your rigid pose. Take regular breaks throughout the day and roll your shoulders, allowing them to relax from time to time for better posture maintenance.
Stretch your back on a daily basis to lengthen your spine, which can help you look taller and leaner. Try a ballet-inspired stretch; stand tall and raise both hands over your head, lengthening your spine. Bend at the waist, keeping your arms straight, and reach down to your toes. Then, reach back up to the sky, arching your back and pulling your abs in for the best stretch.