I was asked this question late last week…
How should I approach on-the-job training?
The best approach to on-the-job training is to structure the training and combine it with other forms of training.
Let’s assume you wanted to teach someone how to measure melt temperature, but you also want them to ensure they do this regularly as part of their job function. For the person to actually use the information, they must know why it is important to measure the melt temperature. As a result, you need to teach the person with three steps 1) explain why measuring melt temperature is important 2) instruction on how to properly measure the melt temperature safely 3) allow them to practice this test themselves.
Basically, demonstration alone does not teach the concepts. You must also teach the employee why something is important… or they will never perform the function consistently.