I made $40,000 a month from 3 income streams during a 4-month cruise around the world—here's how (2024)

I recently took a four-month-long, around-the-world cruise to more than 25 countries and six continents with my husband and baby.

It cost a lot — more than $50,000 — and gave us amazing memories. Our adventure began in sunny Florida and took us through the Panama Canal, then to the beautiful islands of French Polynesia, the stunning landscapes of New Zealand, vibrant cities across Asia and finally to the historical sites of the Mediterranean.

Throughout all of this, I ran my online business, Making Sense of Cents, from the ship. It started 10 years ago as a blog about my progress toward paying off my student loans. Today, I earn $40,000 per month in semi-passive income from it, through three different streams: affiliate marketing, sponsored partnerships and online courses.

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Part of my income also comes from investing: I direct some of my earnings toward personal investing and retirement accounts, and receive quarterly dividend payouts.

I spent roughly two or three hours per cruise day on work — excluding port days, so we could fully explore our destinations — totaling 10-15 hours per week.

Here's what those days looked like, and how I built my income streams to be nearly entirely passive.

I planned my work schedule carefully around our travel plans.

During days at sea — around 60 of them! — I focused on work, particularly during my daughter's nap times. I answered emails, wrote blog posts, brainstormed new ideas, handed accounting, addressed anything urgent that needed my attention and strategized new ways to grow Making Sense of Cents.

I built many of my blog posts around affiliate marketing, a strategy that's responsible for about half of my blog's revenue. I write about products I like and trust, and add a referral link for my readers to check them out. If someone signs up through my link, I earn a commission.

These links can be in posts that I wrote months or even years ago. I can write about a product once, and it can keep earning me money over time. The more traffic I drive to my website, the more even my older posts generate income for me.

Aboard the cruise ship, I published one or two new articles for my blog each week. I also noticed a post from 2022 — 31 Best Stay At Home Jobs (#1 Is My Full Time Job!) — performing well, thanks to a boost from social media platforms like Pinterest and Facebook. Tens of thousands of new readers visited that post during my four months at sea.

Roughly 20% of my revenue comes from advertising, like sponsored partnerships. I team up with a company to promote its brand on my blog or social media, highlighting its products through my writing skills or sharing my experiences with its products.

This content can include reviews or educational posts about what the company offers. It's a win-win situation: the company gains exposure, and I earn money for creating content and reaching my audience.

Before I decide to work with a company, I test out the product or service and do as much research as I can. If I don't like it, I won't form that partnership. I turn down offers every week: companies I don't think my readers would like, companies that don't align with my beliefs and more.

Sponsored partnerships are more active income, so I didn't do many of them during the cruise. Specifically, I worked on some sponsored newsletters, spending maybe five hours on them, in total.

Another 20% of my revenue comes from course sales.

When I started blogging, I didn't fully realize how much money I could make by selling my industry expertise. It took thousands of people — literally, hundreds per week — asking me to help them monetize their own blogs for me to get my first course idea, which ended up being called Making Sense of Affiliate Marketing.

I created the guide I wished I'd had when I was starting out in the blogging world, and published it on an online course platform called Teachable. It explained how affiliate marketing works and how to effectively use it, breaking those topics down into text-based lessons and modules. I still keep it up to date, sometimes even adding new lessons to it.

On the cruise, I updated lessons and answered questions from students. I also manage a Facebook community group for the course, and I made sure I was active there at least a few times per week.

Then, I closed my laptop, sat on the balcony with my husband and baby, and together we watched the sunset right from our room.

Michelle Schroeder-Gardner is the founder of Making Sense of Cents, where she helps readers make smart decisions about how to earn, save, spend and invest. She paid off nearly $40,000 in student loan debt in just seven months and now travels as much as she can. Follow her on Instagram, Facebook and Pinterest.

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