Always push out your chin ever so slightly. Although it might feel a bit awkward, engaging your chin tightens loose skin and gets rid of that extra chin we all carry around.
Work that shoulder. While it tightens the muscle in your arms and makes them appear leaner it also puts body language into a pose. That is always a great addition.
Always accent your body line. If you think of yourself as having an hour glass shape and accent it in your photos you will immediately see a difference. Create diamonds and triangles with your arms as you pose or keep your elbows inside the hourglass line. Either way, remembering to accent your body line in photos is always more appealing then an image where your arms and body are flat.
Let me know if you find these tips helpful or eave a comment with any questions. Happy weekend to all!