Watch the Neighbor Notes online guitar lesson by Jon Herington from Ear IQ: Reactive Improvisation
With a few simple tricks, chord tones can quickly generate real musical ideas that no longer sound like exercises. Neighbor notes are notes a whole or half step higher or lower than a given note, and they're useful devices worth exploring. Try approaching a chord tone from an upper or lower neighbor note. Then try starting with a chord tone, moving to an upper or lower neighbor note, then returning to the chord tone. Also try surrounding a chord tone with both an upper and lower neighbor note: start above, move below, then hit the chord tone, or, to turn it around, start below, move above, then hit the chord tone. Experiment with notes that are a half step and notes that are a whole step higher or lower than the chord tone, listen to how each idea sounds, and use your ear to find the best sounding choice for the effect you're after. Try hammer-ons and pull offs, and slides, bends, and trills with the upper and lower neighbor notes, too. There are all sorts of creative possibilities to discover when you look for different rhythms, too. It's easy to see the infinite variety that can result from all these options, and you'll always be working inside the harmony, since all of these variations are based on the chord tone.