When I was shopping for flights for my July trip from Erie to Oklahoma, the lowest price I found online was $530. I ended up paying $10.

Here’s how I did it:

Back on my return flight from Vegas in March, the flight attendant handed out applications for a Delta American Express credit card. I took one.

I applied for the card and because I charged $500 on it in the first three months, I received 30,000 bonus air miles. I also earned air miles for the dollars I charged. (I have made sure to pay off all the charges each month, which I do for any of my credit cards. I refuse to lose money by paying interest so I don’t make any charges that I don’t have the cash to pay for.)

I already had about 10,000 miles from previous flights banked in my Delta frequent flyer account.

So I combined all the miles and had enough for the 40,000 required for free flights from Erie to Oklahoma and back. I was charged a $10 fee, so my flight wasn’t completely free but it still beat $530.