Can I test out Yosemite on My computer First

[Konagal]

I have Mountain Lion 10.8.5 on both my iMac and Macbook Pro. I am afraid to download either Mavericks or Yosemite. Is there a way to test Yosemite out first on my computer without actually downloading it. I heard it can be done by first downloading to HDD. How would that be done and then test it on my computer. Do I need a clean HDD? Can you tell me step by step please.

 

[simonsi]

Yes - but not without downloading it, but you can test it without altering your existing OS X installation.

Make a backup of your drive if you don't have one.

Download the Yosemite installer and DiskmakerX for Yosemite, use Diskmaker to make a bootable Yosemite USB drive and cmd-option-r boot from that.

Use Disk Utility to create a new partition on your original internal drive, you can shrink an existing partition if there is free space. No data will be lost and DU will confirm this as you go.

Run the Yosemite installer and target the new partition for the install.

When installed do a cmd-option-r reboot and select the Yosemite partition, if you want to make the change for more than one reboot then select the startup drive as the Yosemite partition.

At any time you can cmd-option-r reboot as required into either drive.