Looking for a Qualified Babysitter for 2 Children in Surbiton

I am looking for a caring babysitter to help me with 2 children.
Main responsibility for a nanny would be to pick up kids from school, help them with some snacks or food which was prepared by me in advance and help to the younger one with home work.
I hope to build strong, trustful and respectful relationships with my baby-care-partner and provide flexibility required for both parties :)