There seem to be a lot of questions regarding how to handle a large parrot, especially those macaws with big personalities and huge beaks. Most people who are new to big birds are going to be a bit nervous and rightfully so! The fear of getting bitten (especially in the face) is a big one but knowing how to properly hold your bird is important for his comfort, and yours, and will help you both to earn trust. Keeping birds that we do not trust or know well off of our shoulders is probably the best idea. An insecure macaw will almost always go for the shoulder and may not want to come back down, resulting in a bite, so it is important to know what to do in this situation. Likewise, handling birds properly is something you must learn along with your parrot, there is somewhat of a learning curve. They are naturally inclined to seek the highest place possible and may resist sitting on your hand or arm. They must learn to trust, but you will not likely gain their trust until they feel safe and secure with you.
Many parrots prefer to step up onto arms but the truth is that arms are wide and clothing may be slippery. Parrots cannot get a good grip while perched on an arm and though they think they will be comfortable there, they usually tend to lose balance, and often have to right themselves with their beaks, when a person moves. Arms are more comfortable for us to offer, as they are less vulnerable, than hands and fingers which can easily become crunched. It is easy to see why many people step birds up onto arms when they are getting to know their bird. This is OK, for a while, but as parrot owners we should aim for a more comfortable perch in the future.
If you choose to step your parrot up onto your arm, step him up and then quickly move your arm into an "L" shape with your elbow sharply bent and your forearm in a horizontal position. Your forearm should rest just above your belly button. Hold your arm close to your body so that if your bird loses balance, he or she can
use your body to rebalance himself. Holding him away from your body will make him feel vulnerable unless he is already very secure with your handling. See picture of "L" shape below. This posture discourages your bird from climbing on your shoulder because he now has to grapple up your body to get there. Also, hold your hand in a fist with your fingers and thumb tucked inside to minimize temptation of biting fingers. If you are handling a parrot by stepping him up onto your forearm, never hold your arm up and/or up and away from your body so that the bird is at eye level with you. This is problematic for several reasons: Holding the bird at eye level with you makes him feel like he is more in control of the situation and if he is aggressive he may bite you in the face if he can reach you. Also, holding your arm up, even if it is away from your face, means that your forearm, upper arm, and shoulders are all at an equal level and you have just given your bird a very easy pathway to walk right over to your shoulder with no effort, which he will likely do. He may then decide to not come back down later, or he may decide to take a chunk out of your ear, or give you a new lip piercing. I see these and other improper he regularly when the public comes over to see our adoptable birds.
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Here I am holding Peggy Sue in a sort of "L" shape but my arm is resting on my chest and not my belly and Peggy goes right for the shoulder - so this is a no-no! |
Here I am holding Peggy at eye level but away from my face. see how easily she can just climb right over to my shoulder? |
The very best way to train your parrot to step up is to offer him or her a steady hand while prompting him to step up onto your stiffened fingers. The goal is for your bird to end up with one foot on the inside of your hand (between your fingers and thumb) with the other foot positioned just above the wrist. Hands are more slender than arms and parrots are better able to grip them. Also, a parrot owner can more easily control the mobility of a parrot by clamping the thumb over the birds right foot which should be positioned between thumb and fingers. Once a bird is used to being stepped up like this, he will come to find great security in his new perch as well as being "held" by his parronts thumb. This provides him with both physical and emotional security and deepens the bond between parrot and owner.
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Here is a photo of the position you should have your hand in when offering it to step up. If the bird does not want to step up right away, gently push your hand into the birds breast to prompt him to step up. |
When offering your hand, point your elbow down at the ground with your forearm vertical to keep your bird from stepping up onto your arm or wrist |
Once the bird is on your hand, gently clamp your thumb over the birds right foot. If the bird is not yet comfortable with having it's foot held, work with the bird by touching his feet with your thumb for just a moment while he is stepped up. Casually do this while you have him stepped up and eventually he will become used to the idea. Never force your bird to be held if he does not like it as this will usually result in a bite to make you release the foot!
Some birds will step up with both feet in front of the thumb and then you can cup your hand and wrap your thumb around both feet making them extra secure. This is what it looks like!
Most birds who are just getting used to being perched on your hand and who have a habit of running for the shoulder do best being perched on the hand, with the handler holding the bird out away from the body and away from the shoulder. This time, hold the bird at or just below shoulder level, away from the body but perched on the hand instead of the forearm. Your arm will look like a "V." 
A handler should have elbow pointed down and forearm at a steap downward angle so that the bird feels less comfortable with stepping off the hand and sliding down the forearm. 
Here is a more dramatic "V" with bird perched on the hand, but this owner has his bird perched on the inside of his hand which is much less stable and secure for the bird. He has managed to figure out how to keep the bird off his shoulder though and he can move his arm further away if the bird leans for his shoulder! This is an ideal hold. I have Peggy Sue perched on my hand with my thumb over her foot but she is down at my belly area and off to the side a little bit so she does not feel as "squished" by my body but can still use me to balance if needed for some reason. She is away from my face and it is hard for her to leap up onto my shoulder even when standing tall. as you can see in the picture, she was thinking about trying to get up on my shoulder by stretching, but it was too much effort for her. 
When sitting with your bird, the most comfortable and safe way to sit is to perch your bird on your knee or leg. When I am comfortable with a bird that I know and trust, I will slouch a little by leaning back as far as I can to give my bird extra room. Sitting up straight will keep your belly and chest vertical and will make it harder for your bird to climb. Slouching may result in a bird hiking up your body to get on the shoulder or bite your face. When I have a client who is obese and wants to sit with their bird, I usually will have them sit next to their bird with their bird perched on a low stool or chair as the knee is too steep to perch a bird on. Some people can get away with sitting with their arm in the L shape, down at their belly or resting above their leg with bird perched on hand.