Another aspect is the fact that the first 15 years of your professional career will very likely be the key years in which you will gain the most experience. Beyond that point you will mostly leverage on what you have learned in the first 15 years of your professional life. But it is also very good to be aware of these issues from the beginning of your professional life. This section describes what kind of courses we recommend. It just defines the kind of courses we recommend and why.
Accounting teaches the way companies or people track their revenue and their spending.
There is not specific recommendations on what course to take first or what to take if you want to have only one course. If you wish to pick one course only in all courses mentioned above, I would recommend that you take a course on industrial marketing or on accounting. They are typically done in small groups and you are video taped while talking. The analysis of the tape gives striking lessons on how you behave when you try to convince somebody. They are rare as people often perceive selling as a low-end activity.