[OS X TeX] printing surprises

[konstantinos vasilakos]

Hello, as the subject suggests, is there any possibility that one can be sure about the size of the generated document ?

I want to print this as an A4 size document, is there any command that creates it, or is it by default an A4 size.
As it looks no there is nothing that shows otherwise, it looks ok. 
I want to eliminate any possibility of surprises on the print shop.

Thanks
\K.