I only know how to tame a Cockatiel.  May be the method is more or less the same.

Not sure how young is your bird, the younger it is, the easier to train. I spent the first few days just sitting next to the cage. I took it out for the first time. I used a towel wrap around it, so it won't struggle and fly away. I pet on its head for about 3-5 minutes. And then put it back into its cage.  You need to stick with this towel training until it come to realize you mean no harm to it.

It takes time to tame it down, but in order to tame a bird till it will come back to you, unless the bird was raised from a chick.  The trust needs to be built over time.

The next stage is to finger training by teaching your bird to perch on a stick or your finger. Gently nudge your finger to the portion of the legs. Repeat this routine until the bird instinctively steps onto your finger. 

As with teaching anything, repetition is the key.