Formula back to breastfeeding. (A little long.)

My nurse said I could try breastfeeding again but I just don't know how to transition him back into it. The first day I breastfed my baby three times but he didn't get anything. It made me feel horrible so I switched over. He's now 3 and 1/2 days old and I want to go back to breastfeeding sooo bad. I know he'll get milk this time because they leak non stop. How do you think I should reintroduce my breasts back to my son for feeding? And if some of you ladies have done it, how was the transition?