Switching from breastfeeding to formula

My baby is 5 months old, and I was looking for any advice to wean her off the breast and use formula exclusively. She has been an excellent breastfed baby, perfect latch from day one. I'm starting a new job soon, and I will no longer be staying at home with her to breastfeed her as she needs, so I plan on pumping for a freezer stash and switch her to formula over time. Just looking for advice from anyone who has done this! I'm a FTM, so I'm not sure how to do it, and I'm also very anxious about no longer breastfeeding because I had planned to do it for as long as she wanted to, but life has gotten in the way, and I need to work full time again. Thanks in advance!