These include longer delays in speech, an increased number of pauses & increased speech disturbances. When a person is telling the truth, the vocal tone is likely to be more liquid.
content fabrication - lack of details, a poor logical structure, more negative statements & a general lack of credibility. If a person has had time to prepare a narrative, these indicators will be difficult, if not impossible, to spot.
When a person tries to recall a fact, his eyes tend to move up & to the left. When thinking about the future, his eyes move up & to the right. Thinking about the future involves an act of imagination, as does lying. Therefore, a statement or answer accompanied by an upwards eye movement to the left is likely to be true. This is by no means a foolproof method, but serves as an additional indicator of the truth.
Nervousness is sometimes, but not always, a sign that somebody is lying. Signs of nervousness include fidgeting, a slight raise in vocal pitch and pupil dilation. Always bear in mind that nervousness could be the result of additional factors beyond the truthfulness of a person's response. You ought to think about signs of nervousness as part of a wider lie detection method, than as a stand-alone sign of untruthfulness.