when asking a native speaker their name what is the most common but not overly formal?
Cual es su nombre?
Como te llama?
Su nombre?
I ask this because alot of my friends who are native spanish speakers say that alot of times when people learn Spanish from books they sound too formal and it's sounds weird cause it's not how people really talk.

Question

when asking a native speaker their name what is the most common but not overly formal?
Cual es su nombre? 
Como te llama?
Su nombre?
 I ask this because alot of my friends who are native spanish speakers say that alot of times when people learn Spanish from books they sound too formal and it's sounds weird cause it's not how people really talk.

Answer

In Mexico the most common way to ask people their name is "Como te llamas"

Answer

Normalmente en España la expresión más frecuente es: ¿Cómo te llamas?

Answer

In Spain we say: ¿Cómo te llamas?

Answer

here at Argentina we say "como te llamás?" (....the second A in llamás is accentuated!!!)
btw... while writing ...don't use (¿) opening question mark ..no accents except on verbs that require them (llamás, escribás, acentuandoló... etc) Thanks for learning Argentino!! :-)