There are three virtual labs that you can use to practice without setting up your home lab:

Exploring AlwaysOn Availability Groups in SQL Server 2014

https://vlabs.holsystems.com/vlabs/technet?eng=VLabs&auth=none&src=vlabs&altadd=true&labid=12694

Exploring AlwaysOn Failover Cluster Instances in SQL Server 2014

https://vlabs.holsystems.com/vlabs/technet?eng=VLabs&auth=none&src=vlabs&altadd=true&labid=12693

SQL Server 2012: Working with the SQL Server 2012 Availability Groups

https://vlabs.holsystems.com/vlabs/technet?eng=VLabs&auth=none&src=microsoft.holsystems.com&altadd=true&labid=9919

You can also see more virtual labs here:

https://technet.microsoft.com/en-us/virtuallabs/bb467605.aspx

These are linked from the Microsoft Virtual Academy training that you should also review:

Administering Microsoft SQL Server 2012 Jump Start

http://www.microsoftvirtualacademy.com/training-courses/administering-microsoft-sql-server-2012-jump-start

Tips: review the Virtual Academy training at 1.4 or 2.0 speed because the default pace moves very slow. You can also take some of the assessment tests two times if you miss at least one answer, so I would intentionally miss at least one answer so I could be exposed to more questions during the retake.

Here is another resource I used:

Exam Prep: 70-462 - MCSA: Microsoft SQL Server 2012 from TechEd May 19,2014

https://www.youtube.com/watch?v=7c2FUqUySDE

I passed the 70-462 exam without setting up any of the Hyper-V environments, but I did practice on a single instance, took the SelfTest practice exams and researched everything throughly. I had about six questions to order the correct steps in a process. Good luck!