Transitioning into formula

Kelsie
Hey ladies so at 7 weeks of strictly breastfeeding & pumping Iv decided it's too much when I go back to work so I was wondering how I should slowly ween my little one off breast milk? Tonight for the first time I gave him a 4oz bottle of formula. He seemed to not notice a difference. I'm hoping it also will maybe help him sleep better & a little longer. I have lots of breast milk stored so I'm curios as to how to transition him to just formula. Do I mix the bread milk & formula until my stock pile of milk is gone? And if so how many parts BM and how many scoops?