A Bachelor's Degree is a four year, undergraduate degree in psychology. This degree can prepare you for careers that deal with people, or in which understanding how people make decisions will be helpful, but if you want to do certain kinds of jobs, such as counseling or clinical psychology, you will need more schooling.
If you need more school, you need to decide whether you want a masters degree or a doctoral degree. Many programs only offer a doctoral degree in psychology, so you will want to apply to different programs depending on which degree you want.
A Master's Degree involves two or three years of study beyond the four needed to complete a bachelor's degree, or six to seven years in total. A Masters' in psychology will train you in the basics of counseling, and you may be able to specialize in a particular area. Many organizations employ counselors with Masters' degrees, and having a specialty may be helpful.
One very important thing. If you want to have your own private practice, you need a doctoral degree. In many states it is illegal to run a private practice without a doctoral degree. Masters' degrees generally qualify you for counseling jobs as part of a larger organization or managed care system.
A Doctoral Degree will take you at least four years beyond your bachelor's degree, possibly more. Count on spending at least eight years in school for a doctorate. You can pursue a few different types of doctoral degrees; this can be like specialization at the masters' level, but often the degree you get is different. Pay attention to the type of degree a program offers and its specialization; different programs may offer very different training.
Professional psychology is just one thing that can be done with a psychology degree. A background in psychology can prepare you for many different careers, from advertising or marketing to teaching.
See some of the links below for examples of jobs psychology can prepare you for.
Listed are some important organizations for psychologists; joining and being active in professional organizations can help you advance your career, network, and learn about innovations or trends in the field.
Many more of these organizations exist; listed here are the most general.
Graduate Study in Psychology by 
