Insomniac provides excellent summary of rudiments of voice leading (especially given the abundance of the ii-V7-I progression and variations thereof). This concept is essential in voice leading. The tension/release of chords and what notes facilitate that are what it is. When you're learning to improvise over a chord form, plan out the arpeggios of the chords and play in time just as you would to woodshed memorizing the chords. However, while doing so, plan out where leading tones will run into their respective resolutions. Example: While in the key of C, playing the beginning of a ii-V7-I, start with quarter notes and play the d minor (ii chord) arpeggio with the seventh of the chord (C) resolving to the third of the G (V7) chord (B). In sequence, it would be | D F A C | B... etc. This solidifies the motions of voice leading from ii to V7 in the key of C. Innovate new combinations of resolutions in different parts of the progressions and in different keys. It sounds daunting because that is, essentially, the technical crux of jazz. You will be learning it the rest of your career. As you practice, try it in different keys and rhythms. When you're bored of quarter notes, move on to eighth notes. If quarter notes feel too hectic, try slowing it down a bit or go to half notes. Don't get discouraged. Voice leading will begin to come more naturally once you get a bit of a handle on it; as your ear develops and your aural instinct synthesizes with your fingers.

I just remembered after posting that another good resource for learning a bit of voice leading and chord functions is "The Music of Miles Davis" by Lex Giel. It breaks down a bunch of Miles' compositions and solos into their theoretical components, teaches some basic theory, and you get a little Miles Davis fake book out of it as an added bonus. Find it at a music shop or online.