Adult learners are very different from younger learners. The better you understand your adult audience, the more effective your delivery will be.
Adult education is generally voluntary. The adult learner arrives at class expecting specific results relative to their prior experience and outcomes. Perhaps they're preparing for a new job or they want to become more efficient in their present position. If they summarise that the class won't meet their needs, they'll probably drop it.
To engage an adult learner in training, you must clearly demonstrate the following (sometimes referred to as the three R's)
Another attribute of adult learners is skepticism. Adults prefer to try something out before accepting it. They'll make an effort to retain new information only after they've carefully judged its truth and validity. So promptly engage learners in experiments or activities where they can test out and integrate what they're learning.