Faux pas is French for misstep—and newbie cruisers are apt to make quite a few. Whether it’s failing to reserve an in-demand excursion or packing the wrong clothes, these beginner mistakes can affect your enjoyment onboard and on shore. Here are 10 common mistakes to avoid when booking and taking a cruise.

Not Reserving Certain Excursions in Advance

Your 12-year-old son is obsessed with the volcanic eruption that buried Pompeii, and you promised him you’d visit while in Sorrento; but when you boarded your ship and went to the excursion desk, the tour was sold out. If there’s a must-see sight or place that’s difficult to get to in the allotted port time, reserve that excursion as soon as you book your cruise. You may pay a bit more than if you’d booked independently, but if a sight is more than an hour’s drive from port, a ship excursion is often your safest bet.

Being the Seasick One

How can you be the life of the party if you’re praying to the porcelain goddess? A lot of people discover they get seasick on their first cruise—which is way too late. Once that dreaded, I-want-to-die-now feeling hits, it can take a few days to get back to normal. So, if you’re susceptible to motion sickness (in cars, on airplanes, or at amusement parks), pack anti-seasickness medications or pressure wrist bands and use them at the first sign of ick.

Packing Wrong

You’re celebrating your anniversary onboard, so your wife booked a romantic dinner in the ship’s most elegant restaurant. When confirming your reservation, you realize a jacket is required—but you didn’t pack one and your wife is furious. Check dress codes before you pack (and throw in pants and a collared shirt while you’re at it—some ships don’t allow shorts or tank tops in the dining room at dinner). Conversely, some cruise lines no longer have formal nights, so if you’re a woman you don’t want to be the only one in a sparkly evening gown when everyone else is wearing cute tropical-print sundresses.

Falling for Free Spa or Art Gallery Pitches

As the saying goes, “There’s a sucker born every minute,” and boy do cruise lines know it. On most ships, you’ll experience upsell after upsell. Two to avoid: Free spa seminars, which invariably are pitches for pricy services such as teeth whitening or Botox, and art gallery parties, where you’ll be plied with champagne and coaxed to bid on cheesy artwork.

Making Random Mobile Phone Calls While at Sea

Yes, you’ll be roaming—but at charges that far exceed most per-minute plans for land calls. Before you leave home, check if your mobile carrier offers a cruise ship talk plan (AT&T, T-Mobile, Sprint, and Verizon all do) and a few cover data, too.

Not Checking Port Time Before You Book

You see an amazing deal on a cruise that calls on several places on your bucket list, so you hit “book” and start researching what you want to see and do in each port. Only later, when you look closer at your itinerary, do you realize that you’ll have just four hours in Dubrovnik and less than six on Santorini. Always check itinerary specifics before you book—it might be the reason the price is so cheap.

Skipping the Lifeboat Drill

Yes, those six short blasts and one long blast of the ship’s horn always seem to happen right after you’ve hopped into the Jacuzzi or ordered that piña colada—but don’t ignore it. All ships are required to hold a SOLAS (Safety of Life at Sea) drill before setting sail, so check the schedule in your cabin for the time as soon as you board (it’s usually about an hour before sail away). Cruise lines are required to make sure all passengers attend, so they will find you. 

Confusing Sail Away Time with All Aboard Time

The one you need to remember is “all aboard” time. That is when you need to be back on the ship—typically 30-45 minutes before “sail-away” time. And if your ship is tendering—not docked but anchored offshore and using lifeboats to ferry passengers in—you need to know when the last tender is. (Also, always check that the time on your cell phone is the correct local time.) We know you want as much port time as possible, but you don’t want to be left behind. It does happen and then you’ll be responsible for getting yourself to the next port, which may be an expensive taxi ride or flight away.

Not Doing the Drinks Package Math

If a discounted drinks package pops up while booking, get ready to do the math. Here’s what we mean: If a package is $55 per person per day and you plan to drink more than six beers, wines or cocktails daily, it’s probably worth it. But if it’s an itinerary with long days in port and you can’t imagine drinking that much from dinner until bed time, maybe just running a bar tab is better. Note: Many cruise lines require both people in a cabin to buy the drinks package; some also offer specials that include a free drinks package, so watch for one if you like to imbibe.   

Failing to Secure the Proper Visas

If you don’t read the fine print or ignore emails because they don’t seem all that important, you may end up committing the ultimate cruise faux pas: failure to secure the proper visa for a country on your itinerary. While most Americans don’t need visas for the Caribbean (Cuba being the exception) or Europe (except for Russia, but you can be covered under a ship’s visa and take group shore excursions), countries such Brazil, China, India, Indonesia, Vietnam, and others require them. And it’s up to you to get them before you leave the U.S. or—gasp—you won’t be allowed to board the ship.