I don't like to pay for airfare or hotels so DH and I travel hack our way to miles with credit card application bonuses and spend. In less than 2 years we have over 2 million miles/points between the two of us. No we did not spend that much to earn it. Just our normal day to day spend. paying bills etc.
Some cards we get for the bonus miles and cancel before the annual fee is due. Some we keep and maximize our mile/point earning potential.
We don't carry balances and never use cash or debit cards since neither of those pays me to use them. We pay for everything with credit cards. We do have a few keeper cards.
Chase Sapphire Preferred - 2 points/miles per $ on all dining and travel with an annual 7% bonus given on miles earned. Points transfer 1:1 for United, British Airways, Southwest,
Virgin Atlantic and Korean Air, Hyatt, Marriott, IHG, Ritz Carlton
Chase Freedom - 5 points per $ on quarterly bonus categories. Points can't be used for miles on their own but you can transfer to the Sapphire preferred account and then use them for miles or hotel points.
Chase Ink - 5 ponits/miles per $ on cable, phone, internet and office supply stores. We buy lots of gift cards (Whole Foods, Disney, Macy's etc) at the office supply stores to get the 5x/$ and then use the gift cards when we shop at other stores or pay for things.
Starwood Preferred Guest Amex - Everything else. SPG points transfer to 31 airlines and they give you 5K miles for every 20K you transfer.