Humans are made of Purusa – The spirit and Prakriti – The matter. Prakriti undergoes constant changes and is made of the three Gunas – Sattva, Rajas and Tamas. Mind left in a vegetative or animal state creates a lot of pain, suffering and chains of emotion bound reactions. Thus one should inculcate the Bhavas (attitude) to remain in a Sattvic state.
Everyone is born with two things, one is the body and the other one is the number of breaths (life span). Thus one has to utilize these two things thoroughly and systematically while doing any actions. Duty should be self-directing, first towards self, then towards family, work , society and the nation. This aspect of self-direction towards ones responsibility (Dharma) should be taken with all happiness and a positive state of mind. When an action is done with total integration and attention, it leads to concentration and gaining of knowledge. Thus a self-directed action full life sets a strong base for gaining more knowledge (Jnana), attaining the wisdom of detachment (Vairagya) and finally realizing ones will power (Aisvarya).
Thus the work, i.e. every task, be it in your job, for your family and definitely for yourself, Do it with the sense of Dharma (diligently and with a heart and a peaceful mind).