How do you know when you are in the meditation state?

How do you know when you are in the meditation state

The most common method is by not being able to feel your body.  Your mind is extremely aware and you're in total focus - you just lose the awareness of your body.  Another way that some people can tell is by their arms feeling either extremely heavy, or light - likewise their legs.  Another way that some people can tell is that they can actually feel their REM (Rapid Eye Movement).