When did you sterilize feeding supplies?

When did you ladies sterilize your pump parts as well as the bottles and nipples? I’m 37 weeks today and my plan is to EBF, but I want to be prepared in case I need to pump or we need to use the bottles!

For those that used the Spectra S1, the only part I do not sterilize and wash with each use is the tubing correct? Does the back flow protector also need to be washed/sterilized? The instructions I have says only wash parts that will come in contact with the breast/milk. Sorry if these seem like silly questions. I’m a FTM, so I’m not sure if that piece will or not. I just don’t want to ruin the pump parts!