I just want to share my experience... and you should note that I am not an expert... not even closer
1. Use clicker and teach the bird target training (meaning that it touches the target, usually stick, it deserves reward)
2. move the stick little bit far, so that bird have to step a couple moves to the stick, then reward goes
3. use two perches and start with close gap
4. encourage the bird to hop from one perch to another by pointing the target perch. If done then don"t forget the reward , if failed try to lure it to step up with a close gap, the underlined words is using an approximation in understanding the command.
5. gradually increase the distance, so there will be a transformation from a step up, hop and finally flying.
6. if the bird understand the command, stand between the perches, so it could not see the other perch. Giving the same clue and command but this time pointing at your finger as the target, if not works start all over again from luring him to step up a little bit away then encourage the hop and the same sequence.. flying.
7. using diet training to increase motivation,
8. reward not always be a favorite food, could be scratch, praise and other thing the bird likes.
9. use a close room for training, there will be less distraction for the bird
that's all I know....
ops.. you could also check the article here..http://carlylusflightblog.com/files/Training_Your_Parrot_to_Recall_GoodBird.pdf
Rgds,