Depending on the job your dog does or its health, hand signals may be a necessary part of its life. If your dog is already obedience-trained, implementing hand signals is a simple matter of integration and implementation.
Test your dog for understanding of spoken obedience commands. Give a verbal command with your hands at your sides. If your dog obeys, congratulations. If it doesn't, work on verbal obedience commands until your dog responds reliably from the verbal cue.
Choose your hand signals. Make sure they are easily distinguishable from each other and easy to remember. If your dog must work from a distance, make sure your hand signals can be seen from across a training field.
Begin giving the hand signal directly before giving the verbal command. Continue this process until your dog begins to respond to the hand signal first even though the verbal command will follow.
Wean your dog off the verbal command. Begin giving a verbal command with every other instance, and then every third. Practice this until your dog will respond reliably to just the hand signal with sporadic verbal support.
Phase out the verbal command completely. Always offer praise for a job well done.