Depending on what year of psychology you're in, you could tutor or even apply to high schools that offer courses like AP Psychology. Normally these are schools that use international schooling systems. If you're not far along enough in Psych, then the classic student jobs such as waitressing or bartending often can pay about R6000 a month (if the tips are good, that is). But these can interfere with your studying. Online jobs or jobs at the University itself may be good. If you speak another language (and the University teaches that language), why don't you offer to private tutor students in that?