There are a multitude of computer certification programs available, so how do you decide which ones are right for you? Depending on your specialization and career goals, this may be a simple or extremely complicated decision. Certification takes time and money, so you want to make sure that you are spending it on something that will help you achieve your goals. If you are employed in the industry now, your employer may pay for your certification costs, but you will still have to put in the study time!
Job requirements may make the certification decision easy. If your employer requires that you get a certain certification, then your decision is made for you. Likewise, if there are certifications that almost everyone in your field holds or most employers require, you should start working towards those certifications. The same applies for jobs or roles that you hope to move into in the future. If you don't know whether this is the case, look at some job postings in your field, check resume postings of people in your field and ask people in your area of the computer industry. As an example, if you work as a computer repair technician, you probably need A+ certification. If you want to work in computer security, you probably will need a CISSP (or SSCP if you don't have the necessary related experience yet.)
Once you have achieved any certification that is considered standard in your field, you should look at any experience or education you have that is not verifiable by standard methods. Did you learn something on the job that most people learn in school or a formal training program? Certification is a good way to prove that you have learned the entire standard body of knowledge, not just the parts needed for a particular job. This is particularly important for skills for which you do not have professional experience. For instance, if you are a Windows administrator who taught yourself Linux, a Linux certification like Linux+ or LPIC might be a good idea if you are hoping to get Linux jobs. Likewise, if you've taught yourself the latest version of Windows but your work experience is on an earlier version, certification on that version is a way to prove that you really do know the latest version.
Another thing to keep in mind are easy wins. If you take a class (or even study for another certification), is there a certification that covers the information you studied? Let's say you take a project management class for work or a degree requirement – that wouldn't be enough to get PMP certification (which also has an experience requirement), but you might be able to pass the Project+ exam with little to no additional study. Some vendor certifications allow you to substitute industry neutral CompTIA certifications for some of their requirements, this is like getting two certifications for the price of one. Some degree programs give college credit for certain certifications. This can give you a credential while you work on your degree. If your certification has continuing education requirements, sometimes those requirements can be met with additional certification.
In general, the more well-known and respected the certification program or its sponsor the better. However, if you find that a lesser known certification meets your needs, it can still be valuable to you, just be prepared to quickly and concisely explain the program and why you believe it is valuable. Also, keep in mind that different groups of people respect different things. For instance, in the computer security field, HR is likely to value the CISSP the most, but practitioners often value the GIAC certifications more.
Finally, don't get caught up in a numbers (or letters) game and just go after certifications because you can. Make sure that every certification you have adds value to your resume and skills portfolio. As you prepare for certifications, remember that certifications are a way of validating skills, so make sure that you learn the skills involved, not just the answers to the test questions or you'll only embarrass yourself later.