Many students have a job besides their studies to increase their budget.

The job options for foreigners are legally limited, though. You can find important information about this at the internet portal "International Students" by the Deutsches Studentenwerk (DSW) at the page Jobbing.

The Deutscher Akademisches Austauschdienst (DAAD) has produced a DAAD Information on the Statutory Frameworks applicable to the Pursuit of Gainful Employment by Foreign Students, Academics and Researchers [PDF].

Please do not forget that you have no guarantee for really getting a job! Due to the economical situation in Germany it is becoming harder and harder for students, to finance their studies by working.