For example, you might find a credit card that offers 5% cash back on groceries one quarter of the year, department stores another quarter and so forth. Or, you might find a credit card that offers 4% cash back on gas all year long, or 3% back on groceries.Next, you can look at credit cards that offer bonus cash back for specific spending categories. Some do this on a rotating basis and some do this on an ongoing basis.First, you could look for a credit card that offers more than 1% cash back across the boa ...