The installation involves downloading 13+GB of data – so you may want to run the initial download overnight, depending on the speed of your Internet connection. Once the installation is complete, you’ll be able to delete all of the files required for the set up, but you’ll still be using approximately 13GB of disk space to run IE 9.
You will require approximately 26GB (yes, gigabytes) of free space in order to install IE 9 using the method outlined below.
Important: There are a couple of things you should know before you undertake this (quite easy, albeit lengthy) endeavor.
This detailed guide will take you every step of the way through installing Internet Explorer 9 on your Mac – using nothing but free software.