Citizen by birth moving to UK for the first time; what to do before

I'm planning on moving to the UK by the end of the year; I am a British citizen by birth, but have never lived in the UK before.  What do I need to do before I move?  I've already filled out, but not submitted, an application for my British passport.  I'll have a job & a place to live worked out before I get there, I don't owe any taxes and I won't be making enough money to have to pay US taxes, I'm taking an antidepressant so I'll have to figure what I need to do to find a doctor for that.  Other than that, I'm not sure what I have to do, what am I missing?  Thanks.

Apart from sending in the app and getting your passport I don't know that you need to do anything else.  Make sure you have a couple weeks antidepressants for when you first get there to tide you over until you get registered with a GP.  Basically as soon as you have some sort of official mail with proof of your new address on you can register with a GP's surgery and then you'd see them for the meds going forward.

I won't be making enough money to have to pay US taxes...

You don't say if you also have US citizenship.  If you do, you'll still have to file a US tax return even if you won't owe the US any money in taxes.  If you're not a US citizen, then this most likely doesn't apply to you.

You don't say if you also have US citizenship.  If you do, you'll still have to file a US tax return even if you won't owe the US any money in taxes.  If you're not a US citizen, then this most likely doesn't apply to you.

I am a US citizen.  I was going to file my tax return just in case, thanks though

I am sure you have already gotten one but you need your US passport too before you leave

Apart from sending in the app and getting your passport I don't know that you need to do anything else.  Make sure you have a couple weeks antidepressants for when you first get there to tide you over until you get registered with a GP.  Basically as soon as you have some sort of official mail with proof of your new address on you can register with a GP's surgery and then you'd see them for the meds going forward.

I've registered at two different GPs since moving here, and neither has required any mail with my details on it.  I'm not even sure they asked to see my passport!  Mileage varies with different offices--some of the receptionists are power-mongers that think they rule the world, but if you have medical needs, I wouldn't postpone trying to get in to a GP until you have certain documents--just give it a try.