They say it's important to practice what you preach, and usually I manage to do just that. Case in point: I'm currently saving for retirement, staying out of debt other than my mortgage, and keeping tabs on my investments to ensure they're performing the way I need them to. These are all things I write about constantly, and so I aim to apply that same advice to my personal finances.

But I do need to come clean about one major mistake I made around this time last year. It was on Black Friday, a day I pledged never to shop on. Yet lo and behold, when I opened the fridge that morning, I realized we were low on milk and produce. Since we had the day off and weren't busy, my husband and I decided to venture over to our nearby warehouse club store and restock on grocery essentials. Little did we know that $1,000 later, we'd come home with a new TV and a whole lot of guilt.

Woman with steam coming out of her ears


What went wrong

We started our shopping trip with the best of intentions -- we'd buy our groceries, ignore the so-called sales, and be on our merry way. But as tends to be the case with countless consumers, we fell victim to temptation. The moment we walked into the store, there it was: a glorious new TV that would take our viewing experience to the next level, or so my husband insisted. I was a bit more skeptical, what with the perfectly functional TV already mounted in our living room. But he showed me some comps, and sure enough, the price really was outstanding. And so we decided to plunk down $1,000 on a TV that would normally retail for at least $1,300, and not feel bad about it.

Only I did come away feeling bad about it, because in reality, that TV was very much a want and not remotely close to being a need. And the sad thing? I knew better than to shop on Black Friday because I'd written about the dangers myself. Yet I made the mistake of putting myself in a situation where I'd be more likely to overspend, and while my husband's influence certainly played a role in our purchase, ultimately, I was complicit.

Lesson learned

The takeaway here? If you don't want to end up spending money on unplanned purchases, it's better not to go shopping on Black Friday at all. Even the strongest among us have trouble avoiding temptation, and if you've been known to succumb, your safest bet is to just stay home.

Think about it: I write about personal finance every day. And if I can't be trusted in a retail situation, neither can you.

So this year, make a pact to lock yourself indoors the day after Thanksgiving. And if that's not feasible because you need to shop for specific things, leave your credit cards at home. Had I just taken cash with me that day, I would've walked out with two gallons of milk and a cart full of produce, and nothing more.

Now the good news, as far as my story goes, is that I didn't take on debt to buy that TV. Though I did charge it on our credit card (both for convenience and to snag some cash back on the purchase), I was able to pay the bill off by the end of the month. Most people can't do that, though -- 57% of Americans have less than what our TV cost in the bank. And those are the people who really run into trouble with impulse buys.

Speaking of which, it turns out my husband and I were clearly in good company last year. It's estimated that five out of six Americans regularly make impulse purchases, with more than 50% of consumers spending $100 or more on an unplanned item. And 20% have been known to spend $1,000 or more on a whim. I guess we're now officially part of that latter statistic.

Meanwhile, we're going to be much smarter about Black Friday this year. Our plan is to lounge on the couch, enjoy our Thanksgiving leftovers, and make sure to stock the fridge in advance so that there's no reason to hit a single store that day. We'll probably even squeeze in a movie on that infamous TV. If anything, it'll serve as a reminder not to make the same mistake again.

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