How much space should I allocate to test drive Yosemeite 10.10.3 Beta?

Taz Mangus

macrumors 68040
Mar 10, 2011
Do I have to install another Yosemite onto the 50gb partition before I update or can I just update directly to the new partition?
You first install 10.10.2 to the newly created partition and then apply 10.10.3 update on top of 10.10.2.