returning to work

I exclusively breastfeed my daughter and I'll be returning to work soon I'm trying to get her in a feeding schedule what are some good tips to follow and how often should I be pumping while at work to keep up milk supply?? I also need a goo brand of bottles to use, I tried NUK brand because it was given to me a baby shower but they seem to make her gassy. What is a good brand to use??