The most important thing when training a parrot is to establish a bond with the bird. She/he should trust you in order to follow your commends. Next thing is to keep each training session short - 10-15 mins max. Their attention span is extremely short and they tend to get bored easily. Start with an easy physical exercise as "flapping wings" and give a treat. This is the most preferred way to use a positive reinforcement method. After several physical activities, you can start teaching tricks and after that mimics, sounds, words and phrases. For the purpose of а quality training, always use a comfortable area with minimum distractions. Never raise your voice and make the bird feel like you are playing a game. Also teach and encourage your bird to play with toys, as this is an exercise that engages the mind as well as the body. Everything else depends on the bird. Even if a particular breed is very social and talkative like the Scarlet Macaw

for example, there are some birds that just don't want to talk.