Firstly, complete newbie, only been playing with Raspberry Pi for one day.
So I originally used Noobs to use Raspbian on my Raspberry Pi and I've discovered BerryBoot and want to experiment with adding multiple OSes on a single SD card to see what they're like.
The instructions with BerryBoot (http://www.howtogeek.com/141325/how-to-multi-boot-your-raspberry-pi-with-berryboot/) seem to indicate that I need a fresh SD card.
So does that mean it's impossible to install BerryBoot with an existing installation and that if I want to have multiple OSes I would need to blow away my current installation of Raspbian?
Or is it somehow possible to install BerryBoot and add my existing OS on top of it?