How to install OS X 10.10 Yosemite Public beta on a separate partition - Redsn0w, Redsnow Jailbreak 7.1 - 7.0.3

Yesterday Apple has fulfilled its promise by rolling out OSX 10.10 Yosemite public beta for the first one million applicants. In case you want to install OS X 10.10 Yosemite public beta on your Mac without removing Mac OS X Mavericks, we've got a new and easy way to install each one on a separated partitions.

The benefits are multi-faceted. Number one, you get to try out Apple’s new OS right now. Number two, you don’t have to worry about buggy beta software cramping your style; after all, you’re still running your main OS on the a separate partition. Number three, it can be done quickly, and with little to no downsides (as long as you have the disk space to spare). Check inside for our full tutorial that shows you how to install OS X 10.10 Yosemite on a separate partition on your primary Mac.

NOTE: Before getting deeper in our tutorial, please make sure to have a free space on your disk and If you’re running a Mac with less than 256GB of total HDD space, then I don’t recommend doing this. This warning primarily applies to the lower end Mac’s with SSDsâ€"think the entry level MacBook Air. I recommend doing this on Mac with 256GB~ of total HDD space and above.

Make sure to have adequate free disk space and if your primary OS X instillations consume most of the hard drive space, you’ll need to delete some files, or reconsider your options. If you actually want to be able to use and fully test your Yosemite install, I recommend at least allocating 50GB of storage space to Yosemite partition.

Now you can quickly check out this video tutorial made by iDB:

Download OS X 10.10 Yosemite: 

STEP 1: Firstly download OS X 10.10 Yosemite from Apple's dev portal [1] . Even if you’re not a developer, you can download it via Apple’s Yosemite OS X 10.10 public beta [2] .
STEP 2: Initiate the actual download via the Purchases tab on the Mac App Store app. The download is quite large (over 5 GB) so use patience when downloading.

STEP 3: Once download is completed, go to the launchpad where you will find "Install OS X 10.10 developer preview".

Now the first part is over, let us move to the second one.

Partition your Hard Drive:

STEP 1: Launch Disk Utility, which is available in /Applications/Utilities/Disk Utility.app. You can also find the Disk Utility app by searching via Launchpad.

STEP 2: On the Disk Utility app, you should see Macintosh HD in your list of items on the left-hand side of the app. You will likely see two ‘Macintosh HD’ options. The first one applies to the logical volume, and the second nested ‘Macintosh HD’ applies to the primary partition. Select the first ‘Macintosh HD’ option.
STEP 3: Now click on the "Partition" tab.
STEP 4: Click the ‘+’ sign under the Partition Layout section. This will display a ‘Macintosh HD 2′ partition that can be resized using the drag handle between ‘Macintosh HD’ and ‘Macintosh HD 2′.
STEP 5: Position the drag handle to ensure that the Macintosh HD 2 partition has enough space. I recommend using at least 50GB.

STEP 6: Under Partition Information on the right-hand side of the screen, you’ll see the Name input box. By default the name will be Macintosh HD 2, but I recommend renaming the partition to something that’s easier to identify. Since we’re installing Yosemite, I suggest using the name Yosemite HD.
STEP 7: Ensure that all other settings are left default, including the Format, which should be set to Mac OS Extended (Journaled). Click Apply near the bottom right-hand corner of the screen to create the partition. You will receive a prompt asking if you’re sure you want to proceed. Click the Partition button to continue.

STEP 8: Creating the new partition will take a few moments. Once it is created- you will see another partition Yosemite HD liste under the Macintosh HD logical volume.

Now you have successfully created a separated partition for the new Yosemite 10.10 beta.

How To Install OS X Yosemite 10.10 public beta

STEP 1: Go to the launchpad and click on "Install OS X 10.10 developer preview".

STEP 2: Now click "Continue" and agree for the terms and conditions in order to processed to the installation process.

STEP 3: Once there, click on "Show all disks" and choose Yosemite HD disk.

Switching between operating systems
After the install completes, you’ll be booted into Yosemite. You can easily switch back to your older OS X install, presumably Mavericks, by rebooting and holding the Option key (⌥) as you reboot. You can also use the built in Startup Disk feature found in System Preferences to switch between OS installs.

Keep in mind this is a BETA version, it is stable but it still buggy a lot.. So in case you have faced any problem during using this beta version, no worries.. 

Links

1. ^{^} Apple's dev portal (developer.apple.com)
2. ^{^} Apple’s Yosemite OS X 10.10 public beta (www.idownloadblog.com)

source: www.redsn0w.us