Another vote for Ed's book as well

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He has a book 1 and book 2 on walking bass. What I found is that you can get extremely dfar with just the first book! If you haven't checked it out yet, I recommend it.
It does help to learn to walk over blues...however, what I noticed is that a lot of my students are just not into the blues (even though it is the foundation of most music)...so I recommended this to my students and noticed exponential growth!
First...growth comes through meaningful experiences. The more meaningful the faster you can internalize something.
So what I teach my students that care to learn about walking bass, but may not be so excited about the blues, is:
First: Grab a chord chart, from online or a book, of a simple song that you like! It can be a rock tune, a hip hop tune, any tune! As long as it has a few chords...you'll be in good shape.
Second: I whip out the Ed book and start applying the concetps.
Instantly, I will notice my students enjoying learning walking bass more, because they can even hear its applications to music that actually speaks to them!
Walking bass does not have to be learned in the jazz or blues setting. Walking bass is really just a bassline that is based off of a quarter-note pulse!
Anyway...if you want to get this down fast...that's my recommend! Keep music meaningful and fun and you will learn fast...really fast!