If this is your very first international post, or if it isn't, but you just didn't learn anything the first time, here are some things you probably want to know in advance.
1. You'll miss your stuff a lot.
I know it's hard trying to figure out what to pack, air freight, ship, and store, but take some time to really think about the things that make you comfortable. If there's something you don't feel at home without (like, say, a blanket that doesn't feel like one of those brown, scratchy "Welcome" floor mats), you should pack it in your suitcase. Keep a notebook next to your bed. Make a list of all the things you use during the day. If you do this for several days, you'll have a crazy-looking diary that everyone will armchair analyze if you suddenly snap and commit a crime. You'll also have a good reference for the things you can't live without.
Honestly, you'll be able to live without them, and it will be a great character-building experience, but at what cost? Just pack them.
2. Costco is Great.
Bum a membership off someone, or get your own, and load up on non-perishables for your shipment. You should especially do this if: A) you're not bringing a lot of furniture, so there's no way you'll reach your shipment weight limit, and B) you like to bake. Wrap it up really well. There were bugs all over the sugar bag we brought with us, but none inside (thankfully).
3. Welcome Kits are...
The Welcome Kits provided by CLO are a really nice gesture. I took a picture of what we had in ours. Bear in mind that these are going to vary from post to post. I'm sure you can contact CLO in advance to find out what will be provided in your kit. Ask for it in a nice, non-neurotic way, so you don't develop the reputation of being a horrible person that everyone wants to avoid.
Having a Welcome Kit is hugely helpful, but you should know that the stuff that comes in them will not be the stuff that you've come to love and need. So, as written above, don't count on the blankets being soft. If you need a nice blanket, bring your own.
What I'm trying to say is, you should definitely bring your own bedding. The sheets and blankets are terrible. Really, really terrible.
4. You should take full advantage of your sponsors.
When we heard from Phil's office sponsor, we gave him a very basic shopping list. I thought I would hit the ground running, and be able to do my own shopping the night we arrived. What a joke. Take advantage of your sponsors. Give them a big shopping list. Ask them every question you have. Beg them to drive you to work, until you find your own means.
We had great sponsors when we arrived, and they were indispensable to helping us survive the first week. The office sponsors, especially, are paid for the time it takes them to shop, and set up your house, so it's okay to make them do stuff for you.
5. Figure out your transportation in advance.
I know it isn't always going to be possible to find out about transportation in advance, but try. Start by asking several people whether you'll need a car or not. Athens, for example, is one post where you'll definitely want a car. You can survive without one, but it will make your life 2,000,000,000 times more difficult. To get a car here, you can ship one, buy one on the local market and pay massive taxes, or buy one through the diplomatic pool with a tax exemption. If you choose the last route, you can purchase your car in advance, and save yourself three months of car-less commuter hell. It would have been cool to know all that in advance.
If cars aren't necessary, find out about other transportation options. It's nice to be able to get around from day one (although, really, you're going to be so dead that first day anyway).
6. You can ask to see a list of furnishings before you move.
Different posts have different rules about furniture removal/requests/storage. One way to avoid having five ugly couches and not enough beds is to ask for a list of furnishings in advance, and try to negotiate before you arrive. This is another time when being nice and not neurotic is essential to making a good impression, and getting what you want.
AND, the dining room tables should come with a protective mat. I want you to know that, because we didn't know it, and we don't have one. It terrifies me. I'm so destructive.
7. A dual-SIM cell phone through T-Mobile is a valuable thing.
If you have one of T-Mobile's Simply Choice plans, or whatever they're calling them now, you can get free international data and texting within 140 countries. That is so freaking nice. You can keep your U.S. number, and have a legitimate excuse not to talk on the phone. When you arrive wherever you'll be living, you can buy a cheapo pay-as-you-go SIM to use in country.
I like BLU phones. They're cheap, but nice. The dual SIMs run at the same time (for all intents and purposes--they're not actually running simultaneously), so you won't miss what's happening on either SIM. When you send a text or make a call, you can adjust the settings so it asks you every time which SIM you'd like to use. BLU phones are great.
8. You can play the dumb American to get around town (sometimes).
If you don't know the language, apart from a few key words, don't start conversations with the language as if you do. The person you're speaking with will assume you can speak fluently, and will be anywhere from confused to pissed when you can't. I always lead with English, then throw in a few Greek words during the conversation. I speak as if the person can understand basic English, and use a lot of gestures. I'm always polite and deferential because I'm being super rude in not even attempting to learn the language.
Playing the dumb American will not work everywhere. It helps if you're a woman (sexism), but even that won't save you everywhere. In some places, you'll have to learn the language. In those situations, I guess my advice to you is to start learning before you go, and then try not to feel like too big of a moron when you're using it.
9. It's harder for EFMs.
It just is. If you're the FSO, recognize the sacrifice your family is making for you, and help them with whatever they need to feel okay about that sacrifice. If you're an EFM, and especially if you're not working, be prepared to feel lost and unsettled for about 6 months. It gets better, but those first few months suck.
State is a sweet gig, if you're up for the challenges. As always, feel free to ask questions.Happy Travels!