The same way you quit any of the other times. This is my X weeks notice. Thank you so much for the opportunities I've had while working here.

They may ask, but if you've really made the decision to leave, the why doesn't really matter all that much (assuming this isn't something someone should actually be addressing, like a terrible manager). You can just say you feel this is the right thing for you, you plan to explore new directions.

You don't need a reason, but you will certainly be asked for a reason, so you should have some response prepared.

And actually, the reason you describe above is fair enough -- "a bad fit". If you feel its a bad fit, your boss probably can see it too. And nobody wants an employee who is constantly unhappy in their role. It doesn't benefit anyone in the long run.

Now, if you are good/valuable/been there a long time, they may try to work with you and change your role to something more fitting.
If you are gracious, and give them a couple weeks notice, so they can transition your work, it'll be fine.

Well, for starters, it's not a good idea to quit unless you have something else lined up. The market is not great and many people have spent months looking for jobs and not getting hired. You do not need to give a reason, but it is generally better to preserve good will with people who may be asked to confirm your employment or provide a reference in the future.

I quit a toxic job that was a great fit on paper but ended up being a total nightmare after being there for only 3 months. I gave no notice and didn't care about the reference because it had been such a short time and I had other references. Many employers run background checks on all candidates now, and even a short term job like this will come up on such a check, so it's a good idea to have a story prepared about it so that when you're asked, you have something logical to say about it.

Hi,
Not necessarily, just give 'em 2 weeks notice if u can and if it comes up in convo, just go with you've found another opportunity that will allow for career growth. It's not necessary to be all that detailed unless u just want to, best of luck.

What is the proper protocol for quitting a job?
For various reasons, I've never had to actually quit- I've left jobs, but it was due to moving, or growing out of the position and on to something else- IE concrete reasons.

But at my current position, I just don't like it- that's it. I love everyone I work with though. Do I need to give a reason? I am embarrassed to say that I just don't like it, I really am not good at it, and I just made a bad decision taking the job. Are these 'personal reasons'? Do I need to be that detailed?