The RHCT is a complete subset of the RHCE. In other words, if you're studying for the RHCT, use this book, based on the guidelines listed in Table 2, at the end of this introduction. If you're studying for the RHCE, read the whole book. The RHCE exam includes every aspect of the RHCT exam.
Work with Red Hat Enterprise Linux. Install it on a computer (or virtual machine) that you don't need for any other purpose. Configure the services described in this book. Find ways to break network services and make Linux unbootable, study the characteristics of the problem, and find different ways to fix the problem.
As you go through this book, you'll have the opportunity to install RHEL several times. If you have more than one computer, you'll be able to install RHEL over a network. And you should, as network installations are explicitly listed in the Exam Prep guide. Then you can work with the different network services. Test out each service as you configure it, preferably from another computer on your network. Testing your work becomes especially important when you start working with the security features of Linux.