Hello Jay :) well There are many common expressions: Regards: ¿qué onda?, ¿qué hay?, ¿qué cuentas?, ¿qué pedo?=un poco grosera. Wailing: ¡Rayos!, ¡me lleva!, ¡chin!, ¡mmta!. Others: wey/we= dude, chamaco/a= kid, chava= girl,.... ( I didn't write any bad word) There are slang from every part of mexico, for example in chihuahua people use other words which where I live we don't use. Anyway I'm willing to help you out with all of that if you want it, and you could help me back.. (I´m sorry if I made some mistake)

Hi Jay, The common expressions are very related to the part of the country you comming from. At the north of the country we use words like soda, birrias (beer), que suave (that is nice), while at the south expressions such as "ya se" ( I know) or 'goey' (buddy in a very informal way) are more common. If you want to practice your Spanish I can help you and you can help me with my English. Let me know….