Not my field so can't offer any lab advice, but have you tried an internet search to get a basic protocol? May be then what your supervisor said will make more sense? Other than that, pester all the post-docs and students you can. If there is no one, then grit your teeth and ask your supervisor to jot down what you need to do. He/she will think it better that you confessed that you were confused and were able to see you needed more help, than if you carry on blindly and waste time. Good luck Zara, it's early days and you'll soon get into the swing of things :o)