This should open the floor for those who may not have understood the instructions. Always treat questions with respect - That treatment will engender an atmosphere where questions are accepted as ok and good to ask, thereby insuring your followers will not be hesitant to ask questions and ensure understanding before they begin any task. Too many of us give instructions in words only. Often without emotion or body language as support. It is no wonder we are disappointed in the outcome of the activity.
Human beings are most afraid of appearing silly or dumb.
If an activity has any risk at all of making us look like that, we are reticent to get actively involved. As the leader, you must demonstrate the behavior you desire to provide a visual reference for your followers. Once the behavior is seen, there is little problem emulating it. Be first to do what may be risky. Begin low risk and lead to higher risk - The fear of being laughed at or perceived as clumsy or dumb, is so powerful a force, a leader must be aware of it and work with it to help the followers over come its immobilizing effects.