I’ve worked on a cruise ship for years. Here are 7 things passengers should stop wasting money on.

• I've worked on ships for years, so I compiled a list of things passengers should stop buying.
• It may make more sense to opt for the drink package instead of buying individual cocktails.
• Gym classes and nail services are often pricey and not what you'd expect.
• Visit Insider's homepage for more stories.

Between the shopping malls, specialty dining options, and endless alcoholic beverages, it's easy to lose sight of how much you're spending while cruising.

As someone who has worked on a major cruise line for six years, I've rounded up a list of the seven things tourists should stop wasting their money on.

The gym classes are often shorter and easier than many expect

Many guests try to combat the pounds some cruisers typically gain by signing up for 7 a.m. boot camp.

But these classes are usually on the easier side since every guest has a different fitness level, so if you're looking for a burn, you might be disappointed.

Also, they can get very pricey and are usually shorter than the gym classes you're used to.

Buying individual drinks may cost you more in the end

Your alcohol consumption depends on how wild you want your cruise to be, but buying drinks one by one can add up fast.

Guests often don't think they'll drink a lot, then end up buying six mojitos at $17 apiece in the nightclub.

The beverage package is the way to go and totally worth it if you are going to have three or more drinks per day.

Most onboard nail salons are quite limited

Save yourself the money and disappointment and get your nails done before your cruise.

Many people are used to nail salons that offer extensive services, but most onboard options don't have all the bells and whistles you may be looking for.

Plus the price is always exceptionally higher.

It's risky to book unaffiliated tours

It's tempting to book an exhilarating excursion that's half the price of the ship's, but be wary of unaffiliated tours.

The cruise will wait for late tours booked through the ship, but not for outside excursions.

Plus affiliated tours are run by verified operators. You don't know what safety and security you're going to get when you book independently, so spend your money wisely.

Art auctions aren't usually worth your time and money

As soon as you step on the ship, you're bombarded with art exhibits and raffle tickets to lure you into a three-hour auction where you'll likely walk out with something you didn't need in the first place.

Unless you are serious about art, it's not worth the free glass of Champagne for three hours of your precious vacation.

Souvenirs in ports are pricey

Although everyone wants that Jamaican-flag swimsuit cover-up from the gift shop right off the boat, souvenirs in the ports are pricey since tourists often enjoy the convenience of not having to leave the gates.

But the onboard shops usually have mega-sales throughout the cruise and a huge discount at the end, so you can hold off on buying souvenirs until then.

You should plan what to pack instead of paying for laundry

Most major cruise lines don't have self-service laundry facilities for guests to use, so you usually have to send your clothes away with a stateroom attendant if you want them cleaned. However, this option can be expensive and take a few days.

Since most guests just cruise for a week, it doesn't really make sense to pay for this service.

Pack enough outfits for the cruise, keeping in mind people typically change multiple times a day depending on the activities and events.

Click to read more of my advice on cruising and stories from onboard the ship.