
So, simply choose the appropriate drive which you want to the the default one. There, it will show you the drives where OS has been installed.Open SYSTEM PREFERENCES and then click on STARTUP DISKS.To do that, you need to follow 3 simple steps: But here comes the twist as your Mac has both Lion and Snow Leopard installed on it, and how to set to a default operating system. Just wait the whole installation process is complete and that is it. Select the drive where you want to get the Lion installed. Then, it will prompt you to choose the drive where you want to install it. Now, click on the Lion Installer which will start the installation process. Now, you can use this backup file to get all the data and apps on freshly installed Lion. To use Carbon Copy, choose the source disk as the disk on which SnowLeopard is installed and at target disk, choose the disk where you can to install Lion. Here, you need to have app called Carbon Copy installed on your Mac, which is basically used in to clone all your SnowLeopard apps and data to your Lion OS. This step might not be a compulsory one, but we would recommend this action as it would save a good amount of your time and efforts. Now, since you have the partition, you can go ahead with the further steps to install Mac OS X Lion. If not, then you can click here to get complete guide to create a new partition on Mac. If you have a partition of such free size, then you can go ahead with the further steps.

Now, this makes you have a partition of such size.

So, you need at least of 25-35GB of free space for the installation of Lion OS.

Step By Step Guide To Install Mac OS X Lionįirst thing that you need to do is have a separate partition for your Mac OS X Lion. We bring you the complete step by step guide to complete its installation on your Mac. All you need is DVD of Mac OS X Lion or setup files for Mac OS X 10.7 Lion, then you can kick start your mission to install Mac OS X Lion.
