I have been playing bass for about a year and i think i am progressing pretty well. I am jamming with a friend of mine just drums and bass. How can i take full advantage of this? Should we cover stuff or get a drum and bass book (can you recommend something) or should i stick to what i am doing right now and try and come up with my own bass lines? (Even though they are not so good: I just stick to one scale and i dont really come up with a progression).