What to put back as a nanny

I have recently been hired as a nanny for a family. I know that I am not an independent contractor. They are paying all the correct taxes, but have decided not to withhold federal taxes from my paychecks. I understand that this means I will be responsible for paying them, but I don’t know how much to put back from my paychecks to plan for the large payment at the end of the year.

posted