Service to Bona fide servant (Spiritual Master) of Krsna

The living entities are the marginal energy of the Lord, and therefore they are meant for being properly utilized in the transcendental loving service of the Lord. When this is not done, it is called maya. Therefore the illusion of maya is at once dissipated as soon as one's full  energy is converted in the service of the Lord instead of in sense enjoyment. 

From the personal example of Sri Narada Muni in his previous birth, it is clear that the service of the Lord begins with the service of the Lord's bona fide servants. The Lord says that the service of His servants is greater than His personal service. Service of the devotee is more valuable than the service of the Lord. One should therefore choose a bona fide servant of the Lord constantly engaged in His service and accept such a servant as the spiritual master and engage himself in his (the spiritual master's) service. 

Such a spiritual master is the transparent medium by which to visualize the Lord who is beyond the conception of the material senses. By service of the bona fide spiritual master, the Lord consents to reveal Himself in proportion to the service rendered. SB 1.5.23