Body language is a series of silent signals that play a vitally important part in the impression you give to the world.
Good body language creates an air of confidence and positivity.
It puts others at ease and, according to some research, makes you more sexually attractive.
Negative signals include crossed arms, hunched shoulders and fidgeting. Fiddling with fingers and hair or nibbling your nails will make a thoroughly bad impression.
Positive signals include good posture (naturally sitting up straight), appropriate eye contact (don't stare) and confident hand gestures (no pointing). During conversation, gently leaning towards the other person and nodding occasionally to acknowledge agreement conveys interest. A (genuine) smile is always a winner.