Psychological aspects of professional preparation of students in vocational-training schools are considered with an accent on self-regulation mechanisms of the learning-professional activity. Conditions most favourable for the development of active personality at the vocational training stage are discussed. It is argued that active subjective involvement and, correspondingly, efficiency of activity are related to the image of oneself as a future professional. This image is the more adequate the earlier a student gets involved into the real-life professional activity.