A general therapist, also called a psychotherapist, diagnoses and treats patients with mental or emotional disorders. Depending on your training, the methods you may use to treat your patients may differ. For example, you may focus on changing someone's unhelpful thoughts in a bid to change their behavior, or you may focus on discovering the root cause of certain thoughts.
You must be certified to be a therapist and treat patients. The certification required will be dependent on where you are practicing. Beyond certification and a strong educational background, potential employers will be looking to get an idea of who your clientele usually is. Do you mostly treat couples, children, families, etc.? The experience section of your resume should make that clear. Take a look at this resume, to see what we mean.