I am making french macarons for a friend's baby shower. I know that I will put the macarons together the day before the event in order to give the flavors time to meld. I am hoping to make the shells a few days before that, though. How far in advance can you make macaron shells and what is the best way to store them? I have read that they can be frozen but I am wondering if I can just keep them in the fridge since I will be using them a day or two after I make them.