Hi there mlr99,

• Mac Drive App

Click “Clone” to start the cloning process. The content of the USB drive will be overwritten and replaced with the clone of the boot drive. Booting from a USB Drive. Once you’ve installed macOS on a USB drive or cloned your hard drive to a USB drive, you will need to restart your computer and boot from the clone drive to use it. How do I install OS X on my hard drive using an installation disc? If you have a built-in disc drive, power on your Mac so you can insert the OS X installation disc into the slot. Now power off your Mac from the menu or by holding the power button. Briefly press the power button, then immediately hold the option key while your Mac boots up.

Take a pen drive. Mount it to your computer or laptop; Download the ISO of the operating system you want to install. Install any of the below-given Pen drive bootable creators. Select the attached USB drive and Insert ISO file. And start the flashing process to burn the file of the OS from the computer to your USB drive to produce a Bootable USB. OS X Mavericks is available in the Mac App Store now, but it's only an upgrade—but if you want to do a clean install, you'll need to manually burn an installation flash drive. Here's how to do it. Putting a Bootable Lion Installation on a Flash Drive. This process has a few steps. First, make sure your USB drive is formatted for use with a Mac, then download the OS X Lion installer from the App Store and copy it to your flash drive. Finally, use your bootable flash drive to install Lion on your Mac. Programs that are dragged into the applications folder can safely be installed on an external drive but there are two problems with that. (1) you probably aren't going to carry your external drive around with you so any program on that drive isn't usable when you go on the road. (2) Programs that use automatic updating might not update properly.

From what you describe it sounds like you are trying to install Lion on your newly installed HDD replacement but its not showing as a disk when you try to actually install Mac OS X. That indicates to me that the drive has not yet been formatted as Mac OS Extended Journaled, so it is not ready for Lion to install onto it. This section of the following article will help you get that drive erased and formatted properly so you can continue with the installation:

1. Before you begin, make sure your Mac is connected to the Internet.
2. Restart your Mac. Immediately hold down the Command (⌘) and R keys after you hear the startup sound to start up in OS X Recovery.
3. When the Recovery window appears, select Disk Utility then click Continue.
4. Select the indented volume name of your startup disk from the left side of the Disk Utility window, then click the Erase tab.
5. If you want to securely erase the drive, click Security Options. Select an erase method, then click OK.
6. From the Format pop-up menu, select Mac OS Extended (Journaled). Type a name for your disk, then click Erase.
7. After the drive is erased, close the Disk Utility window.
8. If you’re not connected to the Internet, choose a network from the Wi-Fi menu.
9. Select the option to Reinstall OS X.
10. Click Continue and follow the onscreen instructions to reinstall OS X.

Mac Drive App

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