This study examined the contribution of instructional self-talk and observational learning on the development of long jump technique. Sixty-nine beginner athletes were randomly assigned to four groups: ‘self-talk’, ‘video’, ‘self-talk + video’ and control group. All groups performed 24 practice sessions, consisting of a cognitive intervention program in the form of either instructional self-talk or observational learning, or a combination of both, and the practice of specific drills. A significantly higher performance improvement was recorded for the self-talk group in post test, whereas when kinematic variables of the motor skill (center of mass displacement) were assessed, “observational learning” proved to be more effective. The findings of the current study suggest that young, beginner athletes, participating in complicated tasks, may benefit from cognitive intervention techniques, through enhanced attentional focus on the most critical elements of the motor skill.