What you need to know. What you can use.
1 Know the tune.
1.1 KNOW the melody - listen to singers
1.2 KNOW the changes - listen to piano players
1.3 KNOW the lyrics - listen to singers
1.4 ANALYZE the harmony
1.5 ANALYZE the melody
1.6 ANALYZE the lyrics
2 Techniques - On a single chord
2.1 approach notes
2.1.1 chromatic below
2.1.2 chromatic above
2.1.3 scale step below
2.1.4 scale step above
2.1.5 combinations: 1&4, 1&2, 3&2, etc.
2.2 tension substitution
2.2.1 9 for 1 (#9, 9, b9)
2.2.2 13 for 5 (13, b13)
2.2.3 11 for 3 (#11, 11)
2.3 motivic development
2.3.1 interpolation (insert a note between)
2.3.2 extrapolation (add a note before or after)
2.3.3 retrograde (backwards)
2.3.4 inversion (reverse direction; invert interval)
2.3.5 expansion (wider interval)
2.3.6 contraction (narrower interval)
2.3.7 augmentation (longer rhythmic values)
2.3.8 diminution (shorter rhythmic values)
2.4 phrasing
2.4.1 long vs. short phrases
2.4.2 "sculptured silence"
2.4.3 speech rhythms (poetry)
3 Techniques - Over Changes
3.1 guide tones
3.1.1 3rd & 7th (in cycle 5: 7->3, 3->7)
3.1.2 other chromatic connections
3.1.3 common tones (pedal points)
3.2 walking through the chord-scales
3.3 walking through the arpeggios
3.4 tension-resolve patterns
3.5 lines
3.5.1 target notes
3.5.2 centering a note
3.5.3 compound lines
3.6 motivic development
4 Tell a story!