There are several ways to detect that someone is lying.

Most people who are lying try to create an image of themselves that appears to be good and honest.

 

The biggest "tell" is that the person who is lying talks too much.

 

This video gets into the details of what are the most common "tells" for when someone is lying and has an actual example case to study:

https://youtu.be/pni_kDv9BsU

 

It's worth it for you to view the entire video. This woman works for the CIA and has 20 years of experience in studying the habits of those that lie.

This is a very short post, but if you are too lazy to watch the video the easy take away is that those that lie tend to fabricate big stories. Truthful people tend to give straight forward answers.

So remember that... when an answer seems "too long" that's one of the biggest red flags that the answer isn't "candid".