The first factor you must consider when choosing a self-help course is whether or not a certain course is targeted toward your particular problem. If you have a medical condition or mental illness, you should not try and handle it yourself through self-help courses until you have spoken with a doctor to discuss proper treatment options. Even if you are also undergoing medical treatment, a self-help course could still be beneficial if it is developed using proven theories and methods used by therapists and other professionals in their own practices. Those developed by doctors are often most effective.
It's easy to to get sucked into a self-help course that promises instantaneous or overly dramatic results without requiring much work on your part. Resist the urge follow these plans. It's true that something seeming too good to be true probably is. Keep this in mind when choosing a course, and go for options which have hard work and self improvement over time rather than instant gratification.
You should also choose a course that is designed to help those in your situation. Courses developed by experts in the field are also advised, since they often employ altered methods therapists use in their offices. For instance, if you have obsessive compulsive disorder, you may find a self-help course with information on cognitive behavioral therapy so that you can learn the methods for doing it on your own. You may also use the self-help exercises to go along with your normal therapy routine.
Use common sense when choosing a self-help course. Plans which claim that you can change your life without taking action to do anything differently are not reliable. Some courses use a concept which implements positive thinking with the idea that thinking about something will eventually bring it to fruition. While positive thinking is a powerful tool, it is useless unless you commit to proactive steps to go along with it.
Some studies have shown that patients of certain conditions and those with low self-esteem often find chanting or reciting positive words or phrases to make them feel worse rather than better. If you are doing a course or reading a book and find yourself sliding backward instead of moving forward, consider moving to a different plan.
You should also remember that if you are suffering from the symptoms of depression or if you are engaging in destructive behaviors, it is wise to see a doctor or counselor who is trained in such matters. Even if you do decide to go the self-help route, having a trained professional to guide you in the right direction will increase your chances of success. He or she can also make recommendations for particular therapies, and you can find a course which implements those methods.