If the income of your parents does not suffice to finance the studies, you can apply for governmental support. This financial support is called “Bafög” and amounts to a maximum of 600 Euro. There is the so called “Bafög Office”, which determines the sum you may apply for. For more information contact zib.
If you cannot rely on Bafög, because the income of your parents is too high, and on the other hand you do not want or are not able to burden the budget of your parents, nothing else remains to be done as to work during studying. There are numerous possibilities in Karlsruhe. It is certainly advantageous to search for a Hiwi job (see students' jobs). But you should keep in mind that working part-time may result in a prolongation of the studies duration.
Of course, there are also scholarships which are financed partly from foundations and partly from public funds. More information can be acquired from zib. Some scholarships are confined to specific institutes. Thus, one should check for offerings or web-sites.
Although numerous prizes for advanced achievements in studies are given at the department, it is not possible to finance any study on such a basis.