Step 1
Place your cockatoo in a quiet environment without distraction or outside noises. The idea is to reduce any impediments to learning, to gaining the bird's attention and to allowing the bird to focus on you and what you are attempting to teach him.
Step 2
Stand before your cockatoo and speak directly to him. Speak slowly and clearly and loudly enough to be heard easily. Repeat the same words or phrases every day and try to associate them with actions if possible. For example, if you are feeding the bird you might say "It's dinner time!" several times. This will create a conscious association between eating and speaking that the bird will recognize and copy over time.
Step 3
Talk to your bird as much as possible, running down the news of the day, your schedule of events and whatever else will fill the silence. Your cockatoo will learn by copying your speech, so avoid changes in tone and keep things on an even keel. Teach your cockatoo the way you would an infant, with simple words like "hi" and "bird." Once these have been mastered, try to expand your cockatoo's vocabulary with more basic words. Over time complex words can be added to the mix.