[Auzuigcx]

What we choose to do determines the state of our mind, be it one of suffering or one of peace. For this example, karma = choice. Chosen ways of thinking, speaking and acting.

Unskillful choices are those we make out of ignorance of how reality actually is. These choices lead us to craving for sense pleasures, forming attachments, having views and cravings for eternal existence or annihilation, etc.; in short, these choices lead to suffering of ourselves and/or others.

Skillful choices are those we make with wisdom of reality. These choices lead to dispassion, detachment, non-craving and peace. Following the Noble Eightfold Path and exerting Right Effort in cultivating/maintaining wholesome mental states, while abandoning unwholesome mental states, is a path of skillful choices that leads toward Nirvana (the non-clinging mind).

Once Nirvana is realized, neither skillful nor unskillful choices are required. The non-craving/non-clinging mind has no requirements for continued peace, it will remain peaceful without seeking sense-pleasures or views, and even amidst physical pain and an ever-changing life. All actions taken by the "enlightened mind" are performed with full clarity/discernment of reality and lead neither to pleasure or to pain in regard to mental states.

This is what is meant that an enlightened mind generations no new karma. There is no one to think, speak or act, only conditioned aggregates functioning through cause and effect with the awareness of the causes of suffering fully discerned.