In Yosemity, im downloading ElCapitan and Siera from the AppStore...
1. where are the downloaded dmg files located?
2. how can i make bootable flashUSB drives out of them?
Use this to create a bootable USB drive: http://diskmakerx.com
What if i place the "OSXinstallation" dmg file into a HD partition and then boot from that partition as a startup disk, execute dmg file etc??
Im not getting get what you are saying.You can just drop a random file on a random drive, and expect to boot from that random file. You need to install an OS.
Should be "can't" and not "can". Sorry. Edited the post.Im not getting get what you are saying.