breastfeeding & pumping

My baby is 5 days old. I started out with nursing just about every 3 hours and then would pump right after each feeding. 3 days in it was way too overwhelming. Yesterday I started just exclusive breastfeeding and nursing when he is hungry. My goal is to get to 30-40 mins each feed. I am putting pumping on hold right now but since I will be going back to work and don't want to lose any of my supply, when should I start pumping for a stash and how often? I've heard to pump once a day like in the morning along with other things. Anyone have any inside to this?