When should I start to pump for storage?

My baby is 2 weeks old and feeding well at the breast.  I really do not want to have to give any supplements once I return to work when he is around 12 weeks.  I have purchased a medela pump in style advance so I could start pumping for storage.  

My real question is when should I start pumping and when and how often should I pump.  Should I pump after every feed or just a few times a day?  Right now he only feeds every 3 hours alternating breasts, so could I just pump the breast he is not eating from for that feed?

Any suggestions and ideas would be very much appreciated.

Thanks in advance, Kim

[Tanker Chic]

Pumping alternate breasts sounds like a good plan.  You will be amazed at how fast it all adds up.  

Warning, don't wait to long to start giving him a bottle and do it regularly.  I had to go back to work at 12wks so I started giving my son a bottle at 8 weeks.  He wanted NOTHING to do with it.  He would drink an ounce or two and that was it.  It went on like that for weeks.. it was the most frustrating thing in the world.  Everyday felt like a struggle. I was so affraid he wouldnt' take the bottle by the time I went back to work... I finally had to cut him off from breast feeding completely because there was no other way to get him to take the bottle.  I haven't breast fed him since then. :(   My advice is don't wait too long.  I wouldn't wait past 4wks maybe 6wks. He should be well established at breast feeding by then. I would make sure the takes at least one bottle everyday.  

Best of luck to you..