The Baton/Mace and Whistle Signal System
While watching bands recently, I've seen a number of bands get confused when the drum major gives a command using their mace/baton and a whistle. This happens because the band doesn't understand how the mace/baton and whistle system works.
It's really very simple.
When the drum major blows a long whistle, (usually three to four counts long) the band members should all look up to see the signal the drum major is giving with the mace or baton. The mace or baton tells them what they are about to do. The drum major then blows a short whistle that tells the band to do the command.
The exception would be when the drum major needs to establish tempo, such as when the band begins marching. In this case, after blowing a long whistle and giving the signal, he/she will blow a series of short whistles to establish the tempo for the band.
What each signal is isn't as important as having the band know what each signal means. A baton pointing forwards at a 45° angle might tell the band to start marching. A mace pointing to the right might signal the band to do a right turn. Both hands held above the head in a "Victory V" position could tell the band to begin playing.
Make sure that all band members know what each signal is telling them. Practice giving different signals as they march until they are all comfortable doing each command. This will reduce any confusion the band has while marching on the street.