One of the most important tools for your piano playing bag of tricks is a good supply of left-hand accompaniment patterns. Any time you’re faced with playing straight chords or even playing melodies from a fake book, you’re left to your own resources to supply an interesting-sounding bass line.
TIP: It’s important to practice these patterns again and again to master the right notes and the way each pattern feels under your fingers. The more comfortable you are with the pattern, the more easily you can apply it to any key, any chord, and any scale.