Here are Apple's instructions for creating a bootable Yosemite install disk from an 8GB USB flash drive: Download the OS X Installer app from the Mac App Store. Mount the volume you want to convert into a bootable installer. In this example, I am installing OS X 10.10 Yosemite to the external volume Yosemite 1TB from a Mac that is running OS X 10.8 Mountain Lion. Installing OS X to the external drive volume. A progress bar will indicate the status of the installation of the software to the external volume.
- Bootable USB Stick for macOS X Yosemite 10.10 - Full OS Install, Reinstall, Recovery and Upgrade. 4.4 out of 5 stars 14. USB Memory Stick. Get it as soon as Wed, Sep 1. Mac osx install disk mac os big sur mac os.
- If you have hardware or software that isn’t compatible with macOS Sierra, you might be able to install the previous version, OS X El Capitan. MacOS Sierra won’t install on top of a later version of macOS, but you can erase your disk first or install on another disk.
- Restore the Yosemite installation image to the USB flash drive: Launch the Finder and locate the “Install OS Yosemite.app” file. Right-click (hold the “control” key and click) on it and select “Show Package Contents”. Open Contents, then SharedSupport, and double-click on the InstallESD.dmg (disk image) file to mount it.
Want to learn how to create a bootable USB installer for OS X Yosemite?. Here is the complete step by step guide which you can follow on your MAC create the bootable USB disc. We all know that Yosemite OS X is the latest operating system form Apple, which comes with lots of new features and improvement. If you are interested in new OS and want to try it then sign up for the OS X Beta Program here, which will allow them to test the new OS, if selected.
Once you have the installation app for Yosemite (Install OS X 10.10 Developer Preview), don’t install it directly, other wise you will lose the file and can’t make the USB disc. To get started all you nee a *GB or above USB drive, Apple computer with Mac App Store (10.6.8+) and OS X Yosemite installer.
Create OS X Yosemite Bootable USB Drive
Step 1. Insert the USB drive or Disc on youir MAC and run the Disk Utility app from the Applications > Utilities folder.
Step 2. Now in the app select the USB drive and Selct the Partition Tab.
Step 3. Under Partition Layout, select 1 Partition from the drop-down menu. And enter the Partition information Name: ”yosemite”, Format: “Mac OS Extended (Journaled)”.
Step 4. Click the Options... button and Select GUID Partition Table. After that hit the “Ok” button then “Partition” button.
Step 5. Now the partition process will start and this will take some time to format and making USB drive as a 1 partition
Now the USB part is over and lets move to the OS X Yosemite installer package.
Step 6. Go to Applications again and find the Install OS X 10.10 Developer Preview app that you downloaded.
Step 7. Right-click the installer and select Show Package Contents from the context menu. See the Screenshot below:-
Step 8. Now navigate to Contents -> SharedSupport and open InstallESD.dmg
Step 9. This will start the verify process on your MAC. Wait for some time…….
Step 10. Once the verify process is done you will see the Package Folder.
Step 11. Don’t do anything with this Packages folder just yet. First, we need to unhide the files located in this newly mounted OS X Install ESD image.
Step 12. Launch Terminal.app to enter a command to unhide the file and folder on your MAC.
Step 13. Enter the below mention two commands one by one:-
defaults write com.apple.finder AppleShowAllFiles TRUE
killall Finder
Mac Os X Yosemite Install Disk
Step 14. Now you will see three more files next to the Package folder (Step 10)
Step 15. Switch back to Disk Utility.app to select the partition name created in step 3.
Step 16. Now drag the partition from the device list to the Destination box. Also, drag the BaseSystem.dmg to the Source path
Hit the Restore button.
Step 17. Now a new popup screen appears. From here click on Erase to start the restore process, then enter in your admin password and hit OK to proceed.
Step 18. Once the restore process is done, you will see a new window son your screen. Like the screen below:-
Step 19. Here, open the “System” > “Installation” folders and move the Packages file to trash.
Step 20. Now copy the Packages folder from Step 10 and paste it into the Installation folder that you just opened in previous step.
Step 21. Now Hide the system files again using this command on terminal window
defaults write com.apple.finder AppleShowAllFiles NO
That’s it!. To perform a clean install on your MAC, simply insert the USB drive that you created, power on the computer, and hold down the [option] key to access the boot selection menu. From there, select the USB drive partition, and follow the prompts to install OSX 10.10 on your Mac.
A previous commenter on our How To Speed Up Your Mac article noted that the biggest speed up they experienced for their Mac was to re-install OS X from scratch from a USB disk. Whilst this is a bit disappointing because it’s one of the things I had hoped to escape when I made the switch from Microsoft Windows all those years ago, it makes a fair bit of sense – particularly if you’re one who often plays with software then deletes it again like I do for reviewing stuff, since lots of cruft gets left laying around… (I tried using Parallels Desktop 10 to run an alternative OS X platform for doing my reviews – it was too slow).
The process isn’t all that straight forward and the commenter asked if we would do a How To, so here it is.
The first thing you need to do, as with any major undertaking you might do with your Mac, is to BACK IT UP. Get yourself a Time Capsule from Amazon, eBay or (if you’re in Australia) somewhere like JB Hi-Fi and back up your Mac using Time Machine. Or check out our article about Crashplan if you prefer not to shell out exorbitant amounts of money on a Time Capsule. We can’t stress this enough – you must back up your Mac before continuing. The process outlined below will delete all your data. Everything. Kaboom. So back it up.
While your Mac is backing itself up somehow, go to the Mac App Store and download Yosemite. It’s a big download and if you’re in Australia like me it’ll take a while thanks to our ageing infrastructure and lack of government foresight to get us into the 20th Century of broadband (but I digress into a political debate). DONT OPEN IT. The download will create a link in your Applications folder called ‘Install OSX Yosemite’. Don’t open it yet. Doing so will install Yosemite indeed, but it’ll be an upgrade over the top of what you already have and it’ll delete itself after it’s re-installed. This is not what we want if we’re putting it on a USB. If it opens automatically, simply close it.
You’ll need an 8Gigabyte USB key – which you can pick up at just about any corner store these days.
Plug the USB key into your Mac and if necessary re-format it using Disk Utility so that Yosemite can be written to it. To do this, open Disk Utility, select the USB key on the left and choose the Erase Tab. Choose Mac OS Extended (Journaled) and leave the title as ‘Untitled’ for now. The process of putting Yosemite onto the USB key will rename it anyway.
Now we’re (unfortunately perhaps) going to have to get a little bit familiar with the Terminal application. Open up Terminal (its under Applications -> Utilities if you’ve never used it before). The instruction you need to type assumes you have simply downloaded the ‘Install OS X Yosemite’ application into your applications folder. You’ll need to modify the locations if you’ve managed to download it somewhere else.
sudo /Applications/Install OS X Yosemite.app/Contents/Resources/createinstallmedia –volume /Volumes/Untitled –applicationpath /Applications/Install OS X Yosemite.app –nointeraction
The sudo command at the beginning will ask you for your login password. If your Mac logs in automatically, it’s the same password that you may have used in the pop up windows that occasionally come up when you install new programs.
The createinstallmedia command will give you some (fairly inaccurate) feedback about how far through the process it is, but you can expect it to take anywhere up to 20 minutes depending on how quick your Mac can read from the internal disk and write to the external USB which are typically quite slow. Don’t interrupt the process – don’t turn off your Mac, don’t pull out the USB key, don’t eject the USB key from Finder. Doing so will corrupt the flash key and you’ll need to start again. The process is finished when you see ‘Copy Complete. Done’ in the terminal window.
That’s the hard part over with. Now you need to reboot your Mac ( hope you’re reading this on an iPad or something similar so you can still follow while you reboot! ).
As soon as you hear the Mac bootup ‘Chime’ hold down the Option (or Alt) key and select the USB drive (which should be an orange colour). Double click the icon with the mouse or use the cursor keys to move to that image and then press Enter. This will start the Yosemite Installer, which may take a few minutes depending on the speed of your USB key. When everything is started you’ll see an Installer screen with a number of options. You need to choose the Disk Utility option first of all. If you miss this step you’ll end up just installing Yosemite over itself and you won’t benefit from a fully clean install. When Disk Utility is started click on Macintosh HD (or whatever your internal hard drive is called that you’re going to install Yosemite to) – it’s probably the top drive listed. Just as you did for the USB key, do now for the hard drive – i.e., choose the Erase Tab, choose Mac OS Extended (Journaled) and set the title to whatever you want. This will erase all your files from that disk. Everything. You did backup didn’t you?
Install Yosemite From Usb
Once that process is complete, Exit Disk Utility and choose Install OS X – choosing the freshly erased Hard Drive when the installer asks you.
Once everything is finished and you reboot, you’ll see your shiny new Yosemite install and if your Mac was anything like mine, you’ll probably think you have a new machine too because mine was considerably faster after a fresh install.