How to Spot a liar in seconds

Number 1. The Body language

People who subconsciously pull their body inward when they're lying to make themselves less noticeable. Most people will start to squirm and sometimes conceal their hands to hide fidgety fingers. You should also look at there eyes. People who lie tend to avoid eye contact.
Number 2. Ask Normal Questions

If you ask a basic normal questions, you're able to see a response baseline. Ask about their plans for the weekend or about the weather, anything that's very easy to respond to. The moment they respond, LOOK at their body language and eyes you want to know how they act when they're telling the truth. Do they look left and right or do they look at you straight in the eyes? Make sure you ask 4 questions to see there pattern.
Number 3. Facial Expressions

It's always a easy to tell when people tell the truth or lie due to their facial expressions, though some of these facial expressions are hard to spot. Some people change their facial color to reddish/pink, others will laugh if they tell a lie or bite their lip slightly. Some occasions they will blink rapidly... Each facial expressions change and increases in brain activity as people start lying.
Number 4. The Way They speak

When someone is lying they will always change there tone slightly and slur their speech. Some might start speaking fast or really slowly and with either a higher tone or lower tone. When the sentences they use become more complex as their brain works on overdrive to keep up with their fairy tale.