One of the best travel rewards out there is from Delta Airlines. They offer many ways to earn miles even without a credit card. Of course signing up for the Delta credit card will get you the most miles and the potentially free airline ticket.
Delta Airlines Credit Card
Right now! As of this writing Delta is offering 95,000 miles when you sign up for their top tier credit card. Those miles could add up to a free trip overseas. Once you have the card and start making purchases with the card you will be rewarded with more miles which equal more vacations that do not drain your bank account.
Follow this link for the most recent offerings on a Delta Airlines Credit Card: https://www.delta.com/us/en/skymiles/airline-credit-cards/overview
Delta Airlines and Lyft
Another way to earn more miles is to link you Delta Airline sky miles account with your Lyft account. If you are not a Lyft customer you will get credits towards your next ride. Once you have an account every dollar you spend on Lyft rides will earn you Delta Airline miles.