By CRAIG JOSEPH of NerdWallet
Even if your credit card already earns solid ongoing rewards, there are several ways to rev up those earnings, especially amid the heavy shopping that tends to happen during the holiday season. First, look for lucrative sign-up bonuses when you open a credit card and meet a spending threshold. Beyond that, other opportunities abound — from online shopping portals you can visit to one-time offers you can add to your card as well as shopping strategies like buying gift cards. And the good news is that these steps don’t require a lot of effort on your part.