Summarize the following:
Modeling your hand signals, body language, and facial expressions off of other directors is the best way to understand the kinds of signals to which experienced singers are already accustomed to.  Watch videos of other choir directors online. Watch live performances of professional choirs and focus on what the director does and how the singers respond to each signal. Go to live choir performances and watch the director. Be sure you choose a seat that enables a clear view of the director. Take notes about what seems to work especially well. Sit in on a choir rehearsal and watch the director from the singers’ points of view. Writing down the signals that you plan to use will lead to more consistency when used. Most signals must be exaggerated for your singers to see them clearly—particularly with a large choir or with children. However, try not to exaggerate so much that the audience would be distracted by your movements. Direct in front of a mirror or videotape yourself directing and determine whether your signals are clear. The more you practice using your directing body language, the more comfortable you will be doing it in front of an actual choir.  Play your favorite choral music and pretend that you are directing it. If you know another choir director, ask if you can “borrow” their (already trained) choir for a part of a rehearsal. Then ask for feedback or tips from the singers or the choir director.

Summary:
Watch other directors. Make yourself a “cheat sheet” of signals. Go big. Watch yourself directing. Practice frequently.