@LauraJ83 First, I'm very envious. Wish I was going back again this year! I'm realizing that I failed to post my trip report here. Sorry!
If you are at all prone to car sickness I highly recommend you take Dramamine before the drive up. It is a series of switchback (over 50 of them) and it is notorious for people stopped alongside the road to puke.
Which hotel are you staying in? Make sure to make your dinner reservations for each night when you check in. They'll likely tell you this but don't blow it off. I'd suggest you try each of the restaurants at least once. Same with any special activities, make reservations as early as possible. For lunches we just ate at the restaurant at the base connected to the main hotel. If you like avocado be sure to order it with your hamburger because they give you a huge amount!
If you can, stop in Santiago and buy wine and snacks for your room. We had a fridge in our room to store but it was small. Liquor tends to be pretty expensive you buy it from the hotels although you should absolutely have a ginger pisco sour or two (or more) if you like ginger. They are amazing. Speaking of Santiago, if you'll be spending any time there let me know if you'd like ideas for restaurants or things to see. I lived there long ago but have been back a couple of times recently and can give you a few recs.
As far as the mountain goes, navigation is fairly easy because you can see most everything. Be aware that their poma lifts are a bit jerky and took me clean out on one load. My arms were sore every day from managing them. The poma lines were pretty orderly but the lift lines were chaotic, similar to Europe. Lots of people pushing past you then getting through the gates and waiting for their friends who didn't manage to get by you. So annoying. Chileans are late risers so early morning starts are rare for them meaning the mountain is empty for the first hour or two. It also means the snow report doesn't get posted until what seems to be very late for those of us in the US. I see this morning's was posted at 8am.
Be careful going into powder fields as their are many hidden rock fields. My friend got taken out by a couple of hidden rocks. Definitely ski as light as you can. If you get a powder dump the nice thing is that so many people there don't touch the powder that I was finding untracked lines for 3 days after ours. We were fortunate because the snow came in overnight on our first night there and then we had bluebird days until we left so we didn't have to battle visibility and flat light issues. If you do get a powder day you might consider doing a private lesson so you end up with a guide for the day. I considered it but my travel companion was on a tight budget.
They encourage you to drop your skis/boots in a storage room at the end of the day. Personally, there was no way in hell I was leaving my boots in that chaos so they came upstairs with me which confused the attendants but oh well.
Feel free to PM me if you have additional questions as I don't check in here much these days.