I pump into the storage containers that came with my pump and transfer it to a bottle and then store the excess in the fridge or freeze it using the Medela storage bags. Depending on how much you produce you may not be able to pump enough ounces for a full feeding at one time or you may produce more than is needed for an entire feeding. When I first brought my baby home, I only gave him 2 ounces at a time as a newborn. If you don't make enough, you'll want to collect the milk and store it in the fridge till you have enough for a bottle, and if you make too much you'll want to of course save the excess for times when you can't pump.
Medela also makes a feeding and storage set where you can pump directly into the bottles and then attach nipples to the storage container. This would be a good option for you and I have found that the nipples and the collars in this set are compatible with the other storage containers produced by Medela. While this is convenient, and especially great for travel, I have found better luck with switching to Born Free or Dr. Brown bottles when it comes to feeding because the Medela nipples have a tendency to collapse and the bottles don't have any sort of venting mechanism to keep the nipples from collapsing. Baby also ends up swallowing a lot of air this way. But everyone is different and different things work for different people. You really just have to experiment to see what works best for you.
A GREAT resource for pumping moms is the Exclusively Pumping Message Board on IVillage.
http://messageboards.ivillage.com/iv-ppexcluspump
Lots of great insight from moms who exclusively pump, not sure if that is what you plan to do, but even if you plan to supplement with formula and/or nurse directly from the breast you'll still find helpful advice. I was not successful at nursing, but have been able to give my baby breastmilk for 4 months through exclusively pumping. It's not easy so if you need any extra pumping advice send me a message and I'm happy to answer any questions!
Good luck!