Hmmm....Well strangely, posture has a lot to do with projecting confidence. Stand up straight and tall with your chest puffed out (but not looking rediculous like you are about to fight someone, just looking like your spine is straight and your shoulders are squared off), this type of posture always conveys confidence.
Also "every girl's crazy 'bout a sharp dressed man". NOT sharp like ZZ top though, what were THEY thinking? Sharp like the guys in Men's Health magazine ads. You can have your own funky style, but it has to be sharp. No strings hanging off seam lines, pants hemmed at the correct length (slight break, not too short, not too long), hair cut and in place, shoes that are expensive (even if you have to save up for them and only have a few pairs, its better than several pairs of junk shoes), if you wear glasses make sure you have cool looking frames that compliment your face, your outer wear should be sharp too - flannels are only ok when camping! Dressing sharp speaks confidence.
Also, *speaking* itself can convey confidence. When you speak, make sure you clearly enunciate and project your voice (without being too loud). A soft spoken man seems unconfident to us.
And then finally....smile. A smiling person looks like a happy person, and a happy person is usually confident.
