1. Flash a genuine smile (one that forms crinkles at the corners of your eyes and mouth). It is disarming and has been proven to boost your mood.
2. To ace the handshake, focus on firmly directing the up-and-down movement instead of on the palm squeeze. You’ll avoid fish hand and the death grip.
3. Even if you’re not holding a drink, gesture in that same general zone. Keeping hands in front of your chest makes you seem bold and assertive. Keep feet shoulder-width apart, and point them at the person you’re talking to. This will give you a solid stance as well as an open posture.
Source: Body-Language Expert Lillian Glass, PhD