CALLING ALL MOMMAS!!!

I have recently been hired as a full time nanny for a very young baby. Although I am confident I can care for the baby, this is the parents' first child and they are understandably a little nervous about leaving their child alone with someone they don't yet know very well. I have done my best to reassure them that I take my responsibilities very seriously, but I want to hear from the moms out there. I would love advice, babysitting tips, things to calm jittery parents (and jittery babies). Any and all advice is welcome.