everyone lies from time to time, may it be a big fat lie or just a small white lie. Even so, nothing good can come from repeatedly lying to someone. However, these are certainly not foolproof. Saying whether someone is lying or telling the truth is as risky as forecasting next week's weather.
Again, these signs are hardly foolproof, but we believe you'll find them helpful. Below are steps on how to tell

Being suspicious: Someone who is lying may be smiling, be looking nervous, or even just being suspicious. Sometimes they may take a while to answer a question because they have to make up a lie. But in truth you never really tell if they are lying. Be careful these characteristics are also those of a very shy person so don't accuse some one of lying.
Eye contacts: Notice the person's eye movements. Contrary to popular belief, a liar does not always avoid eye contact. Humans naturally break eye contact and look at non-moving objects to help them focus and remember. Liars may deliberately make eye contact to seem more sincere. You can usually tell if a person is remembering something or making something up based on their eye movements. When someone is remembering details, their eyes move to the right (your right). When someone is making something up, their eyes move to the left. It's usually reversed for lefties.
Uncomfortable: This is as a result of unusual body language, liars usually taps their foot a lot, fidgets with their hands, raises their shoulders, turns away from you or brings their hand to their face (to touch their chin or nose, etc.) -- in other words, if they act nervous or uncomfortable -- it could mean they're telling a lie.
Sweating: Check for sweating. People tend to sweat more when they lie. But this is not always a reliable indication of lying. Some people may sweat a lot more just because of nervousness or shyness.

Repetition of sentence: Notice it when sentence are being repeated. If the person uses almost the exact same words over and over, then it's probably a lie. When a person makes up a lie, he often tries to remember a certain phrase or sentence that sounds convincing. When asked to explain the situation again, the liar will use the very same 'convincing' sentence again.
High pitched: The voice becomes rapid and/or high-pitched. It may be unsteady too. Liar may speak in a single tone (monotone), spluttering out their words, and fail to emphasize pronouns like "you" or "I" as we do in normal conversation. They may omit the pronouns altogether.
Delay in responses to questions: Listen for a subtle delay in responses to questions. An honest answer comes quickly from memory. Lies require a quick mental review of what they have told others to avoid inconsistency and to make up new details as needed. However, when people look up to remember things, it does not necessarily mean that they are lying.

With the above steps I believe you can now spot someone who is lying and most of these characteristics also goes along with someone who is shy

Author's Bio: 

Chonyui Kevin is the main experts behind www.xhow2.com. He is some one who has studied and figured out how to complete so many kinds of tasks, both simple and complex, day-to-day part of life, and is now willing to share his knowledge and age experience with you. By combining the experiential knowledge of certified experts with the practical knowledge of everyday people, we will help everyone complete any task.If you think this is some kind of marketing hype, then see what others are saying about us http://www.xhow2.com/testimonials.htm