Step 1: When you click on setup, it shows the minimum required space which is 8.95GB and if you agree to the license then click on the checkbox and click the Next button.
Step 2: After clicking the Next button it will ask for optional features to install. If you want all features then click on the checkbox to select all, then click the install button. Otherwise if you want to go back then click on the back button.
Step 3: A window will be opened and it will show the acquiring and applying process.
Step 4: Wait for completion of the acquiring process; once this is completed, the applying process is started and the components of Visual Studio 2012 begins to be applied on your system.