What steps did the narrator take to get Ranga married to Ratna?

He took various steps.He made Ratna sing and Ranga listen to her purposely so as to attract Ranga's attention to her. He first made her look hard to get by declaring her as married. Then he made Ranga believe that he was sick and plotted a scheme with Shastri to make it look as if he was sick because of a girl named Ratna and this was proved by horoscopic calculations and by careful use of shastra through shastri ji. All this attracted Ranga to Ratna and the narrator's last act of going to Ratna's house and enquiring ( he had pretended to do so) about her marriage juts sealed the deal.