For every 1 minute of content delivered, design in 3 minutes of practice. Highly transferable training gives participants large amounts of time to practice what we want them to do on-the-job. New skills that are not adequately practice have lesser chances of being transferred. I suggest that you set a minimum of 3 to 1. For every 1 minute of content, at least 3 minutes of practice. I like more than 3 to 1, but consider setting this as the minimum design ratio.