Para-language,
or aspects of the voice apart from speech, such as pitch, tone, and speed of speaking;

Closeness or Personal Space (Proxemics),
which determines the level of intimacy;

Eye Contact,
where the amount of eye contact often determines the level of trust and trustworthiness;

Facial Expressions,
including smiling, frowning and even blinking;

Posture,
or how you stand or sit, whether your arms are crossed, and so on;

Physiological Changes,
for example, sweating or blinking more when nervous.

Body Movements (Kinesics),
for example, hand gestures or nodding or shaking the head