The correct answer to this open question is the following.
Keeping a journal about what is good and bad regarding my summer or part-time work is a good idea to help me choose a career path because writing down what I like and what I dislike, I can get a pretty close idea of the things I enjoy and have more skills to perform, compared to the things I do not like or I have no abilities at all.
If a clearly identify my skills and abilities in the workplace during the summer, it will be easier for me to identify what could be the profession I love or at least, what I am attracted to.
As it is difficult to remember all the work experience by memory, writing the journal will help me to remember exact dates, specific activities that I enjoyed or were interesting, and what was not.