[airline rewards card vacation]Courtesy of Liz Knueven * I really needed a vacation earlier this year, but I had no idea how I'd afford it. * Luckily, I had opened a United Explorer Card a year before and earned the sign-up bonus of 40,000 miles. That bonus helped me take a vacation to Greece and Italy. * While I'd always thought airline miles and travel rewards were too good to be true, I found out that they're incredibly valuable, and I won't go back to another type of card anytime soon. * See Business Insider's picks for the best rewards credit cards » The start of 2019 found me in a rather precarious financial situation. I was a freelancer living in Seattle, an area with incredibly high costs of living. While I still made more than the job I left to freelance, I didn't make enough for the area. I never knew when money was coming in, though I knew when it was going out. It was always feast or famine, and I felt like I'd been on an emotional roller coaster.SEE THE REST OF THE STORY AT BUSINESS INSIDERNOW WATCH: How to find water when you're stuck in the desert SEE ALSO: * After opening my first airline credit card a year and a half ago, I can't imagine using my debit card ever again * My car insurance company raised my rate by 20%, but after an hour of research I kept it anyway — and I learned 2 important lessons along the way * Thanks to points from my Amex Gold card, I saved my parents $2,400 on booking a same-day flight