Having explained that selflessness is the key to freedom from reaction (Text 19), Krishna now explains how to begin and eventually perfect selfless action.
Tyaktva karma phala sanga - Renounce attachment to the fruit of your work
One cannot become selfless overnight. We are deeply attached not only to the results of our work, but even to the work itself and the types of work we enjoy or dislike to perform. To start out on the path towards selflessness, however, Krishna advises practice of detachment from the results of our work. We can accomplish this by not hording those results for our own gratification.
Nitya tripto nirashrayah - Always independently satisfied
How can one relinquish the fruits of one's labor? We have plans, and need those fruits to achieve those plans. Krishna therefore mentions that, as one attempts to relinquish the hard-earned fruits of his labor, he should try to cultivate a spiritual independence that enables us to be self-satisfied, and freed from the need for elaborate material development.
Karmani abhipravritto api - Although very active...
One who can give up attachment to the fruits of his work becomes liberated. Although he is very active, it can be said that "He does nothing at all" (naiva kinchit karoti sah) because his actions, being freed from selfish desire, produce no reaction and are thus equivalent to inaction.