Upgrading your SQL Server 2014 Evaluation to Full Version

I installed Microsoft SQL Server 2014 a couple of months before on my PC, but now I suddenly found that the evaluation period has expired and a message appears when I try to open SQL Server Management Studio:

Evaluation period has expired. For information on how to upgrade your evaluation software please go to http://www.microsoft.com/sql/howtobuy. I seem to find a easy solution to this problem.

The outcome that I wanted to achieve here was to upgrade the existing SQL Server instance.
The procedure to do this upgrade is as per the steps below:

1. Run SQL Server setup from the installation media, and SQL Server Installation Center.

2. On the SQL Server Installation Center, click on Maintenance (left side), and then click on Edition Upgrade.

3. Continue setup until you reach the <Product Key> stage. Now, insert the license key for the corresponding edition you are upgrading to.

4: Accept the license terms.

5. Specify the instance of SQL Server to modify.

6. Verify the SQL Server 2014 features that will be changed and then press <Upgrade> option.

7. Do not lose your patience at this stage here since you might just have to wait for a couple of minutes without having to do anything but to wait for the next screen to appear. (I nearly aborted this process at this stage when I felt like it was not happening as expected. )

8. Finally, you will reach <Complete> stage, where the screen appears as per below.

I hope this was helpful. Comments and feedbacks are welcome.