Watch the Chord Substitution: 2 online guitar lesson by Fareed Haque from Bebop Improv Survival Guide
Principle 2: Lead to any chord with its own dominant.
For ex: we can take our ii-V-I in C and lead to Dmt with its own dominant A7. we can even shuttle between a chord and its dominant as much as we want, and have time for, before moving on to the next chord. dm7 - G7 -Cmaj 7 can become A7 - Dm7 to A7 to D7 to G7-D7-D7-Cmaj7-G7-C7! All coming from adding dominants and leading dominants to a simple ii-V-I in C!