The best thing recommended while being in Sri Mayapur is chanting the holy names of the Lord. It's recommended in the scripture that for Kaliyuga, the current age of iron quarrel and hypocrisy the most powerful mantra to be chanted is the Hare Krishna Maha-mantra, i.e. Hare Krishna Hare Krishna Krishna Krishna Hare Hare, Hare Rama Hare Rama Rama Rama Hare Hare. This maha-mantra is chanted 24x7 in Sri Mayapur and one should participate in the Kirtan congregational chanting of the holy Namesas much as possible.
One should read spiritual books like Srimad Bhagavad Gita, Srimad Bhagavatam and Sri Chaitanya Charitamrita depending on their level of spiritual advancement. ISKCON's founder-acharya His Divine Grace A.C. Bhaktivedanta Prabhupada has left for the world a great treasure of spiritual knowledge filled with pure devotion, and every person visiting this place is strongly recommended to read his writings for adding further benefit to his or her visit to this most sublime and powerful spiritual environment on the planet.
Taking Prasadam food offered to Lord Krishna is another important activity one should perform here. Prasadam is not only karma-free but is filled with the Love of Godhead.
Hearing Krishna katha glories and pastimes of the Supreme Personality Godhead is immensely beneficial.
Hare Krishna Hare Krishna Krishna Krishna Hare HareHare Rama Hare Rama Rama Rama Hare Hare