Disclosure: This post is for informational purposes only. I am not a licensed lactation consultant and the opinions reflected in this post are based up on my own experiences.
If you wish to continue to breastfeed, you will need to invest in a good quality breast pump. Find a breast pump that meets your needs and budget. (Note: if you plan on pumping multiple times a day, its wise to spend a little bit more money and get a better breast pump to avoid frequent replacements)
Now that you found the breast pump that meets your needs, you should begin to learn how to use the breast pump before returning to work. This will allow your to learn how to properly use it, once you return to work things will be more stressful and your body will not be accustomed to using a breast pump. It is important to relax as this helps your body produce more milk. Learn how to properly store expressed breast milk using the storage guidelines, storage solutions, and how to thaw and warm expressed breastmilk.