The best babysitters are generally those recommended by friends, people that have already earned someone's trust. However, finding a babysitter in Valencia shouldn't prove too difficult, since there are a lot of non Spanish speaking people who are actively seeking work with an English speaking family, as an au pair, nanny or part time babysitting.
If you are either looking for a babysitter or offering babysitting services, post your details on the Valencia Connect Classifieds page.