Definition of Karma Yoga in Bhagavad Gita
Do your duty to the best of your ability, O Arjuna, with your mind attached to the Lord, abandoning worry and selfish attachment to the results, and remaining calm in both success and failure.
The calmness of the mind is called Karma-yoga. (2.48) Working to the best of one's abilities without becoming selfishly attached to the fruits of work is called Karma-yoga. (2.50)
One is given the power and the ability to do one's respective duty in life, but one is not free to choose the desired results. To work without expecting success or good results would be meaningless, but to be fully prepared for the unexpected should be an important part of any planning.
Do your duty in life ¾ to the best of your ability ¾ as God's personal servant without any regard for the personal enjoyment of the fruits of your work.
Devotion in Bhagavad Gita
The word Bhakti comes from a root word “Bhaja” in Sanskrit which means to remember, contemplate, worship, serve, adore, love and sing the glories and greatness of the creator.
If you are unable even to do any spiritual discipline, then be intent on performing your duty for Me. You shall attain perfection just by working for Me (as an instrument, just to serve and please Me, without selfish motives). (12.10)
Thus Karma-yoga becomes Bhakti-yoga when it is done with God consciousness.
Self-Knowledge in Bhagavad Gita
Just as one sun illuminates the entire world; similarly, the Supreme Being illumines --- or gives life to--- the entire creation, O Arjuna. (13.33)
The eternal individual soul (Jeeva) in the body of living beings is, indeed, integral part of the Supreme Being. It associates with the six sensory faculties of perception --- including the mind --- and activates them. (15.07)
Jeeva transmigrates into 8.4 million species of life on the earth as long as it remains in bodily concept due to the veil of ignorance created by Maya. Jeeva attains salvation when one obtains the transcendental knowledge, discussed above, that he or she is not this physical body, but Atma, and an integral part and parcel of the Supreme Being.