First and Foremost to me Ты Should Be patient as еще as Ты can yes ,you need ,studying will improve your skills but Ты don't have . Ты can get it by luck if Ты Любовь kids.
Ты need a Child Care qualification Level 1 and2. Here to be a qualfies child minder Ты need those 2 qualifications but just to be a normal babysitter CPR is a great advantaged and to be trusted and known well by the childs parents is a good thing too. Think it just all depends where Ты live in what qualifications Ты need. but the best thing Ты need to babysit is to be trustworthy and patient with kids.
Well, I don't know about other countries, but in Quebec we need to take a babysitting course, which is about 4 days in length (I'd say 2 hours per day...? Not sure, I forgot). After that, Ты need a babysitting test which covers all that Ты learned. Finally, Ты get a certificate! From the Canadian Red Cross!