Have you had any general studies lessons at all - that should give you a clue?
General studies is generally regarded as 'the exam you can't study for' so don't worry too much. It usually contains sections on science, society and culture and rather than needing to remember anything specific you will need to be able to analyse texts, argue a case for something, discribe various concepts etc. The exam is usually based on various issues and current affairs so you could expect things like teenage pregnancies, the middle east conflict, gene therepy to come up. It is recommended that you do no revision for general studies but instead have a good knowledhe of current affairs from reading the papers and things though letts and other companies do produce revision guides and things.
find out what your board is and download a few practice papers from their website.