I can tell you what I do with Foo. I've had Foo now for about 3 years, and though she is mostly a sweetie, she has her moments or days as the case may be.
It will become easier when you are able to read him better. I don't hang out with Foo when I know she is in one of her moods. She's out all day and is flighted. So if she is in a really bad mood and flys to me and then bites I tell her no bite, or be gentle, she knows what both means. If she doesn't I put her back on her cage or her play gym and ignore her. If she is persistent, and flys back to try again to bite (which she hasn't done in a good year or more) I put her in the cage and close it. I'll walk by every few minutes and say Hi Foo. If she is being calm and happy I take her back out and if she is being sweet usually give her a treat. This is where reading them helps a lot, I can tell when she is still in a bad mood, including the difference between she can come out and hang out on her cage but isn't going to be super f un to really hang out with and when she is back to her normal sweet self completely and can come hang out with me. This just takes time to know the little differences.
If your's is so bitey that you are getting bit while trying to bring him back to his cage or some other perch other than you, you can use a towel. Find what works best with yours and then stay consistent. These guys are really smart, but if you are not consistent you may end up sending mixed messages.
If yours is just biting too hard by accident because he doesn't understand how soft you are, same rules really apply, though you might encourage him to chew on something else-like a piece of cardboard, or other toy that is ok to bite hard.
Discipline may cause them to get even more angry, like your earthquake method. Think of it like a small toddler, it can be a battle of wills. Be consistent and you will win and your conure will be happier for it.
You are going to want to pick the best methods that you and your parrot are comfortable with and then stick with it. That goes for both discipline (like putting them on a time out perch) and giving praise for good behavior (like a piece of millet).