Make sure you get a GREAT surgeon who does tons of these per year. You want an expert, not just someone who can do it.
Get all your research done in advance. Buy a bunch of books, and start printing stuff off the internet. Clear you calender. Make disability arrangements. Make sure family knows...you are going to be busy healing, and its going to be precarious...one day your are up ...the next down. It may 6 or 10 months to be fully yourself again. Now THIS may not be your case you may bounce back quicker, and not have any troubles. Let hope you are one of those.
Just in case you have some set backs:
Make sure all your SIGNIFICANT relationships are put on hold, with all the grace you now posess, since later you won't have it...and you will be embarassed and mortified by your own behavior.
Any...big decisons, about cars, houses, career...etc. needs to be put aside...or taken care of now. Just because its not chemo therapy, doesn't mean you'll be presentable.
Make sure you don't minimize this. Its a journey like you have never been on, and people will think you look fine, when you will still be very out of it. They may judge you, mock you, and demean you. Protect yourself now.
Also, find a doctor now...who you like who will follow you properly. You want someone who knows that upper part of ranges feels good, is willing to test the frees, and knows that hypothryoidism is tricky, and sometimes you'll need extra help figuring things out.
Make sure doctor will let you have Armour if you chose it. Some are dead set against it..particularly in the case of cancer...which in my opinion is the very person who needs it most. You will be to weak to fight...so find a advocate that will stick with you through the entire hairy mess.
You won't be able to drive a car...because you will be out of your mind. Its called dimentia....and it feels like you have been separated from yourself. You may hallucinate, and feel like no one is on your side. Some refer to it as hypo hell. And, with very good reason.
The surgery is easy, compared to afterwards. You are better off prepared.
I'm telling you this NOT to scare you but to look out for you. Nobody gave me the heads up, and I've paid dearly. So, I'm giving you what I didn't have.
Please keep this in mind:This is not the kind of trip where you can have faith and just "figure" things out as you go along.
I know its a lot to take in all at once...but I couldn't NOT be honest. Remember though, not every one goes through the same thing I did. You may have a wonderful time, and be glowing in no time.
So there you have it...good luck!