Sorry to hear he's being a little nipper. My 3 have quite different personalities and have different types of relationships and interactions with me. This means I typically handle their time-outs slightly differently.
Bella
Constantly wants to be on me
Eventually gets nippy if energy not channeled through constructive training
Is scared of /attacks most man made plastic hard toys
Chews and shreds soft natural toys in cage
Defensive of food bowls
Great flyer
Begs to come out of her cage
Usually steps up
Dexter
Likes contact (but gets amorous)
Gentle bites to indicate opinion
Can enjoy playing with toys or exploring without humans prompting
Minimal shredding of in cage soft natural toys
Not territorial
Good flyer
Squawks for human attention when left in other room
Usually steps up (unless in amorous mood)
Gerry
Likes verbal attention and company but will become agitated if not let out
Lunges and bites (but getting better)
Likes foot toys but becomes anxious if out of cage and can't see human
Religiously chews and shreds soft natural toys in cage
Defensive of cage
Can't fly
Paces in cage if human present to indicate desire to come out
Rarely steps up unless he wants to go somewhere
With Bella and Dexter, if they give a small but unpleasant nip, they're told "no biting" and get put on a boring tree stand, and I turn my back on them for about 20 seconds. No other verbal communication at all. If they fly to me or leave the tree stand during the 20 seconds, I place them back - not saying a word, no eye contact.
Then once the 20 seconds is up, I ask them to step up, if they do, it's "Good girl" or "Good boy" and back to normal...
With Bella I'll get her to step up different places, get her to turn around, get her to fly to me, lots of "Good girl" and some treats. As she is driven by being with me and interacting with me.
With Dexter he gets to play with toys, as if I fuss him too much and do too much physical activity with him, he gets amorous and constantly tries to 'love' my hand.
The idea is that they learn that nipping me equals boring.
Doing what I ask equals my company, and/or fun and treats.
If after the first nip, I try to get them to step up, and they're still nippy, I tell them "no biting" and repeatedly put them on the boring tree stand for 20 seconds. I don't say anything else to them. If they bite harder, I put them in their cage in their room, they're told "no biting" and get put straight into their cage. I leave them there for upto 10 mins. Please note, it is the being in a separate room to the human and the fun, and not the caging itself that is the time out. Bella hasn't learnt 'stay' yet, so any attempt to remove her from my person is futile as she'll just fly straight back to me.
It's important that upon my return after the 10 mins that I act like it never happened and focus on now. So it's back to step ups and treats etc.
With Gerry it's a little different as he's not flighted and is a plucker. I believe his plucking is anxiety based from being caged during his previous humans holiday. The fact that he won't step up for me all the time means it's harder to control his movements to and from the cage. His flightlessness also means he is more likely to stay put. As timing is important for the birds to learn associations between actions and reactions, I have adapted to these factors for Gerry while trying to reduce his stress in these situations.
Gerry is usually in or on his cage, or on a table stand. His nips only come about from me trying to get him to step up. If he nips, he is told "no biting" and I turn my back on him and ignore him for 20/30 seconds. Then I try again. I repeat. I allow gentle beaking and will talk to him softly during, but nipping too hard equalls "no biting" and being ignored.
I hold a treat out over my arm or hand as bait for the step up. If he makes positive physical contact or one foot on, he gets positive reinforcement via verbal "Good boy"s or treats. While he gently beaks me, I stroke and scratch his beak while saying" Beak". This contact means he gets used to me touching his beak and doesn't find it threatening. So if he does nip too hard, I can use my fingers to free myself from his grasp without him being shocked or scared or additionally defensive with regards to my digits.
As one of my training items - I also touch Bella and Dexter on the beak after saying "Beak". They learn what to expect and understand the contact that's about to take place. I find that by creating a repertoire of words with associated actions, the birds become more comfortable as they understand what is happening around or to them.