Employers must document all training. Creating a training matrix will help keep track of who has been trained, when they were trained, the training topic, and when it is time for refresher training. Employees must also sign an official sign-in sheet provided by the employer that can serve as proof that employees received proper training. The sign in sheet must have a broad description of what is being covered in the training. Tests or quizzes on the presented material can help gauge employee understanding of the material and highlight topics that need to be reviewed.