Just seeing this thread, thought I'd give you another perspective. Some is in line with the wonderful advice you've already received, and some goes a different route. Take a look and see what works for you.
First thing. Learning the reason/trigger for the bite, coupled with learning body language enough to recognize when one is coming, is key. Avoiding the bite before it happens is best. As Noodles had mentioned in one of her responses, biting is usually the last resort in communication. Birds communicate heavily using body language. Far more so than we do as people. As such, they are usually at a loss by the time they bite us, wondering why the heck we didn't pay attention to all the warnings given beforehand.
That said, while most bites are a communication fail, others are the result of bad habits that have inadvertently taught your bird to bite.
So my first advice is to check out this thread in its entirety:
http://www.parrotforums.com/training/57935-brainstorming-biting-parrots.html Its focus is on bite avoidance, which is ultimately what you want.
Second, I'd advise checking out these threads on bite pressure training:
http://www.parrotforums.com/training/63988-bite-pressure-training.html
http://www.parrotforums.com/questions-answers/58911-bird-bites-always-2.html
Personally, I view the whole parrot raising endeavor as a lifestyle you build for your bird. Everything interwoven. Here's how I do it.
1) I don't free feed (leave food available all day long), but rather provide large meals at defined mealtimes. (What the heck does that have to do with biting? Bear with me, and remember what I said about everything being interwoven.) By providing meals at defined meal times, I both avoid the potential for obesity, and provide times between meals where my birds will be more treat-motivated. And this is time that can be used for training.
Understand, this is merely strategically-timed training.
Not withholding food to get desired behavior. I abhor the practice of withholding food. Strategically-timed training means you work with your bird when they are at their natural hungriest, between meals. That way, you can train them with positive reinforcement, using treats to reinforce behaviors that you find desirable. Because the most effective way to train a bird is by
getting them to want what you want. It's most effective because it helps build the bond between you, and eventually takes away the aspect of a battle of wills. You don't want to train via domination. End of the day, I believe that to be counterproductive to the relationship.
How do you get them to want what you want? Association and consistency. Association is key, because that is how birds learn. They do something right, you praise and then reward with their favorite treat. (A treat they can't get at their meals. A treat they only earn by doing you want them to do.) Soon enough, they not only associate the good behavior with the treats, but also the treats with the verbal praise. Which makes the verbal praise something they come to find valuable in and of itself. (Which becomes important later, so you don't have to reward every single good behavior with a food treat every time for the rest of their lives. Sometimes, verbal praise can be enough. But that comes later.) And finally, they come to associate time out with you with the yummy goodness of their favorite treats. The association train links it all together.
And consistency, of course, because that is the only way to cement the association in their minds.
2) Defined meals in defined spaces. Specifically, their big, defined meals are only provided in their cages. (Treats, of course, can be offered anywhere.) Why? Association. If their cages are the only places where they get their fullest food contentment, they come to associate their cages with satiation. They come to see their cages as their home. A place of shelter and food, rather than as a prison. Why is this important? Well, aside from wanting them to enjoy their cages (toys are important for this as well), it also allows you to use them as a timeout space.
A few posts earlier pointed out that you should avoid using the cages as a timeout space, as the bird may develop an aversion to their cage. And the psychology behind this is sound. Buuuuuuut, if you establish their cages as hearth and home via association strongly enough, that never becomes an issue. I never have to try to catch my birds or force them into their cages. Ever. Despite the fact I do put them in their cages anytime a timeout is required. (Though nowadays, our communication has reached the point that I never have to put them on timeout anymore... except when Jolly is feeling a little too amorous and needs a minute to cool his hormones.)
Point is, when the cages come to solidly represent a place of food contentment in their minds, they don't see it as a bad place to be. I've kept 3 ekkies and a cockatiel. Never an issue with the cage.
3) Okay, the biting. As I'd mentioned earlier, bite avoidance is key. Again, as Noodles said in an earlier post, perching on the shoulder is a privilege, not a right. It has to be earned. He currently bites your ear, so the shoulder is off-limits until he knows better. And be consistent with this. It will be hard at first, as birds can be STUBBORN. So, yes. It will be a battle of wills... at first. But you are clearly defining your boundary. This is important. You're not as skilled in conveying your desires via body language as a bird is, so consistency becomes your best tool.
That said, what to do when there's a 'bite-avoidance fail' and your bird bites? Well, two things. First, and this is probably the biggest point of departure with advice you've already been given: remove that beak! Never go with the 'don't react' approach. Now, this must be controlled, of course. Because there is a basis for why people think you shouldn't react when bitten. Basically, if you go into histrionics when they bite, you could either trigger a fear response, or they might find your weird squawks amusing and, like any good little scientist, seek to reapply the stimulus in order to reproduce the results. In this way, you'd be reinforcing the bad behavior.
So instead, you would say 'No', in a firm, yet even and
controlled voice. If he continues to bear down, use two fingers to leverage - pincer style - near the point of the beak. Done correctly, your two pincer fingers will slide down to the point of the beak and interpose themselves between his beak and your flesh. Your movements should be smooth and steady. No jerky movements to frighten him. And the pressure applied should slide your pincer fingers downward rather than applying any pressure on his beak that could prove hurtful. It works. If I've used this with ekkie beaks, it'll work with conures.
Added benefit? Using your fingers pincer style protects you from a potential second bite, as it would be those fingers he goes after. But if you've kept them together, when he goes for them you can just allow them to separate and his beak won't find purchase on anything.
Why do I say you should remove the biting beak? Because they have to understand that the behavior is unacceptable. It's not much different than a baby/toddler. If they bite you, or clock you with one of their toys, you don't just take it stoically, do you? No. The child is doing it because he/she doesn't know better. So you stop them from doing it and explain that it is wrong. 'Not nice' and such. And that is how they learn.
Once you've removed the beak, your little guy goes on timeout. Immediately. Do not pass Go, do not collect $200. (If the Monopoly reference is lost, here, never mind. Lol!) Where? In the cage, which he should be associating with hearth and home given the defined meals aspect we discussed earlier. See how they all intertwine?
When taking them to the cage for timeout, I always moved differently than how I did when bringing them to the cage for any other reason. A more purposeful stride, and in complete silence. (The cold shoulder) And once he's in there, you leave the room entirely. Or, if that's not feasible, you turn your back completely and move as far away as you can. No eye contact! Maintain this for five minutes, then let him back out. Wash, rinse, repeat. And I cannot stress enough that consistency is key, here. He may very well come out and immediately bite you again. This doesn't mean the technique has failed. It just means he needs another five minutes on timeout to build further on the association. It could take days or months. Be consistent.
Oh! And never bring any of your annoyance with you from the prior session into the next. Every time you take him out of timeout, it's a new slate. He can tell if you're holding a grudge, and that kind of body language on your part could inadvertently trigger a less-than-desirable reaction on his side.
On the flip side, when he behaves in a way that is desirable, you reward the behavior. Yummy goodness reinforces said behavior. And they'll eventually get to the point where they look forward to doing the things you ask of them.
And finally, do some training with him. Sounds like your guy is flighted. If you target train him, and then recall train him, you can start doing flight drills with him that will tire him out a bit. Sometimes having too much energy can make a bird more prone to bite. Like a child pent up in a house for quarantine might be more likely to break a statue because they're full of energy and bouncing off the walls. (Yes, I'm talking about one of my children. Sigh...)
Here's a link on target-training in case you're unfamiliar: [ame="https://youtu.be/HaOicTtwIZo"]Beginners guide to target training parrots - YouTube[/ame]
As for recall training and such, let me know if you have any questions on that as well. I've already gone on too long, so I'll cut this short. (Relatively speaking. Lol!)
