If your participants are logged into Call Manager, they can use the Raise Hand option found in the bottom right corner of Call Manager and the Moderator on the call will see those who have raised their hands. This can be an effective and orderly way of managing participation on the call. Participants can lower their hand anytime by click on the Raise Hand icon.
Once you have raised your hand, there is a visual indicator as seen below which is associated to your 'business card' in Call Manager. This makes it easy for the Moderator to see who is asking a question.