How I spent $1,230 on convenience in just 2 months

Millennials are workaholics: There's even a survey in the Harvard Business Review to prove it. Research shows young people are more likely to work longer days and give up unused vacation days out of fear that will make us seem replaceable, costing us a raise, promotion or our jobs.

It makes sense to optimize the hours we have left in the week to make life simpler and more convenient. After a tiring day at work, my peers and I often opt for convenience over financially-sound decisions.

As a 24-year-old woman starting her first full-time job, there is still a lot I have to learn about time management and budgeting. For me, convenience means I sometimes skip my bus ride and Uber home, avoid cooking by ordering takeout, and head online to buy beauty and lifestyle products.

When I ran the numbers, here's how much I spent on these different forms of convenience over just two months this summer.

Public transit & ride-sharing: $623

The 2015 song "Uber Everywhere" has rather satirically become one of my anthem songs. Although I don't literally apply the song title to my daily life, I use the service way too often for my liking. And I'm not alone.

Uber is gaining millennial customers at a faster rate than any other brand in the U.S., Business Insider reports based on a survey of over 1,000 brands from the YouGov BrandIndex.

From the beginning of June through the end of July, I spent exactly $381 on Uber and Lyft rides. My median ride cost $9.52, which doesn't feel like that much. It's cheaper than most New York City lunches.

But multiply that by 40 rides in two months and the total grows. Considering I also spent $242 for monthly unlimited MetroCards, I felt quite irresponsible.

I'm not alone. Last year, a millennial peer of mine at CNBC Make It spent nearly $700 on rides in one month.

If I keep up the pace of my last two months of using ride sharing apps, I'll wind up wasting over $1,000 by the end of December. But I won't. Since I started bullet journaling in July and keeping track of my expenses, I've been better about using public transportation and my total should be far lower.

Dining out: $487

Since I find myself dining out at restaurants or at family or friend's homes, I have barely made an effort to buy groceries. It turns out plenty of people around my age find themselves doing the same.

Millennials spend 47 percent of their food dollars, or $3,097 a year, on going out to eat, Food Institute CEO Brian Todd tells CNBC Make It. Based on U.S. Census Bureau and Bureau of Labor Statistics expenditure data, the Food Institute creates a yearly "Demographic of Food Spending" report, and this year's millennial spending on food away from home is up from 44 percent the year before.

From the beginning of June to the end of July, I spent about $487 on food, with less than half of the purchases of $10 or less and the rest $15 and up. This puts me on track to spend as much as most millennials spend each month. I can do better than that.

Going forward, I aim to spend less by cooking more meals at home.

Subscription services: $20

When millennials aren't eating away from home, there is a chance they are using meal delivery kits to make dinner. Services like Blue Apron and HelloFresh, ranging at $60 to $130 a week, deliver the ingredients to your home to save you a trip to the market and provide the recipes to go along. Last year, Blue Apron made between $750 million and $1 billion in revenue, Bloomberg reports.

Though I don't use those food services, I am subscribed to one beauty service I discovered a few years ago in college, where there were no department stores in my town.

For $10 a month, I received five or six product samples, which would often included my personal essentials and a few "fun" products I wouldn't typically seek out. Aside from this service, I spent less than $50 in the last two months on personal care.

In 2016, Mic reported that these subscription services specifically target millennials because of how curious we are about trying new products.

"This business is about the art of giving to yourself," Marshal Cohen, chief industry analyst at NPD told Fast Company in 2015. "Millennial consumers, in particular, love the idea of self-indulgence, and subscription companies really understand this."

From splitting the check to DIY adventures, "Young Money" helps you navigate tricky financial situations.

Check out more in the series:

• A couples therapist says this is the best way to talk about money with your friends
• 4 monthly expenses I'll never spend money on again
• Roommate horror stories that will inspire you to sign a 'prenup' before moving in together

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