Manah Siksa and the section about 'Anartha-nivrtti' from Madhurya Kadambini - understand these very thoroughly. After this, when lust, anger, greed, attachment, pride and envy will go away then one will not commit offences to the holy name, Vaisnavas, while doing seva, etc. Only then can one enter the pastimes of Mahaprabhu. And after entering the pastimes of Mahaprabhu, then entry into the pastimes of Krsna will be possible.