Here is a simple double tap exercise to make the bass more interesting.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgjit6_P-4bqan8ovopM1bhIDWDe9vEjsGP8blVvnTQipMKE5PWBHOPPY2_3iv52xncKhhBr3pbWrAwCcqIOI8b2HILfes2JUCWIRwcOLzOUQ-L5AZt9vw8tTO-anvxQRvnWn1qnQ/s400/doubletap.jpg)
Use your right hand (index and middle) fingers to simultaneously press on the 12th fret D and G string. Play around with rhythmic patterns.
Hope this exercise will help you explore more ways to create music with bass.
Cheers