Watch the Sunny Side Up online guitar lesson by Andrew Ford from Essentials: Walking Bass Lines
First thing to notice is there are a lot of roots on the first beat of the chord changes. This really anchors the band and helps to hear the chord progression. The first bar is a C chord and we simply play the chord tones which are C, the root, moving down to the major 3rd, E, then the 5, G on the E string and finally back to the root C that transitions using a half step movement to the B note in the next bar. Bar 2 has a 2-5 progression in A minor. Over the B minor 7 flat 5 we simply play the root twice without outlining the chord which is perfectly acceptable and for beats 3 and 4 over the E7 chord we use the neutral chord tones E and B, root and 5. What I mean by neutral is that we could have used these same 2 notes had the chord been EMaj, maj 7th, minor, minor 7th, suspended or a number of other chords. Next we have an F chord where we use primarily chord tones but add the 6, the notes are 1, major 3rd, 6 and 5, F, A, D, and C. Again we have a smooth transition to from the C to D, our root in bar 4. Here again we play 2 quarter note roots for the Dm7 chord and over the G7 we play the root, G, and 5, D, using swinging 8th notes and end on a quarter note chromatic passing tone, Ab. In bar 5 we have an Am7 chord and here we do a simple walking pattern consisting of 1, 2, 3, and back to 1. Our last 1, A, moves by a 1-4 relationship smoothly to D in bar 6 which is our root, in this bar we have a diatonic walkdown from D, to C, to B, and then A. We have 2 chords again in bar 7, actually bars 7 and 8 form a 2-5-1 pattern. So we begin with a 1-5 movement for the 1st 2 beats, D to A, and then 1-3 in the second half, G to B. Then we move up a half step to C, down to the major 3rd, E, down again to D, the 2, and finish with the 5, G. Now we repeat that 8 bar chord progression with new notes. In bar 9 we have the C chord again this time we start on the 5 and walk down the major scale but use a ghost note in between the first 2 notes, G to F, we continue walking down to E, the 3, and D, the 2 then another ghost note using the A string. We use only roots in bar 10, two B's to two E's, simple but does the job, all about the feel. Bar 11 starts on the root, F, walks down to E, continues to D, and ends on the major 3rd, A. We sort of imply a D minor chord on beats 3 and 4, Dm7 is closely related to the F chord. In bar 12 we go back to playing roots only, G, and G# or Ab, we spice it up with a ghost note in there but again it's really about the feel in this case, not the complex or fancy notes you can come up with. In bar 13 we again begin with the root, A, move to a ghost note on the A string, walk down the triad to E, C, then the root A. We repeat our same pattern from bar 6 in bar 14, D, C, B, A. Over the 2-5 in bar 15 we start with the root D, minor 3rd, F, then G to B, root, third over the G7 chord. This time when we get to the 1 chord, C, we do a walk down that implies a chromatic descending chord progression, C, B, Bb, and A. Next we have the bridge section which starts with another 2-5-1 progression in bars 17-20. Bar 17 has another scalar type walk down using the scale based on the Gm7 chord which is the Dorian scale, we start with G, the root, and walk down to F, the b7, then E, the 6, then the 5, D, we keep that descending motion going by playing the root, C, or our next chord, down to Bb, the b7 of our mixolydian scale, A, the 6, and G, the 5. We actually walk down one more note, to F which is the root of our chord for bars 19 and 20. Bar 19 repeats our pattern from bar 3, bar 20 starts on the 5, C, goes up to the 2, G, down to F, the root, then a chromatic connecting note, Eb that leads us to bar 5 of our bridge, the D7 chord. We do a more simplified walk down here starting on the root, D, to the b7, C, to B, our 6, then repeat the B before encountering another 2-5, A-D. We simply outline both chords in bar 22 with the corresponding 1-5, for Am7, A to E, for D7, D to A. In bar 23 we get a little more colorful over the G7 by starting with the root but walking up chromatically to Ab, then to A, the 2, and finally down to Eb a chromatic note that takes us to D, the root of our next 2-5. Here in bar 24 is a familiar 1-3 movement, D to F, then to the root G, down to the 5 but an anticipation which is often done to accentuate a new section or returning to a previous section, in this case going back to A. Now bar 25 begins our final 8 bars of the phrase. Our anticipation note, C, holds over until the second beat of bar 25, we then play E, the major 3rd, G, the 5, a ghost note on the A string and then back to the 1. The next bar starts on the root, B of our Bm7b5 chord, then we play the b5, F, and finish with 2 simple E roots. Bars 27 and 28 are repeats of bars 11 and 12. Now we have the last 4 bars, the first one, bar 28 starts with a familiar motif from bar 13, the root, and ghost note and then the 5, E, but then goes to the root down an octave and up to a chromatic note, Eb that leads us to the root, D, in bar 30. The pattern here is root-5-root-3, D, A, D, F#. This walks up to G, the root of our next chord change, even though we have a suspended to 7 chord the pattern works over both chords, its the same one we played in bar 17 even though that is over a minor chord, they share some of the same scale notes. Our last bar resolves but also sets up the top of the phrase again with the G7 chord. Our notes here are root-3 over the C chord, C to E, and swinging 8th notes over the G7 chord starting on the 5, D, to low E, the 6, and finally to G, the root, as a quarter note.