Having a CCNA will greatly increase your chance of a successful job interview and make your CV stand out to the competition as it shows that you are fluent in basic networking skills and principles. It shows a thorough understanding of computer network concepts and how LANs and WANs not only work, but also how they fit together.
Learning how to achieve the qualificaition is the first step and applying your mind to the necessary study and revision is a task in itself. It is all well and good trying to read as many books on subject matter as possible however this is never going to let you get the knowledge and more importantly, the understanding, required to pass a CCNA exam. Hands on practice is an important skill to have and being able to set up a lab environment will help to see how things fit together and work.
To start with, if you can get hold of one or two old Cisco 1800 or 2600 routers and a network switch then you are half way to getting a decent lab environment set up. This will help demonstrate the routing side of the CCNA course involving topics such as OSPF, EIGRP, RIP and other routing protocols.
If it is possible to get two switches (of the 3500 + variety) then it may also help you understand switching concepts along the likes on setting up and implementing VLANs, Etherchannel technologies and so on. If you are lucky enough to be able to have a Cisco 3560 switch or better then you will also be able to investigate topics such as high availability technology in the form of HSRP and GLBP protocols. Even the smallest about of hands on experience will be better than none and the reason being is that if it is possible to apply theory into practice then the more will go in and stay in.
Of course one of the best forms of learning are the official books from Cisco which contain all the course matter necessary to pass the exams. They mark in the key topics involved and also test you section by section in your knowledge before the topic starts so it is possible to see what areas need to be worked on to make it sink in.