Babysitting advice for a 5 month old?

i am babysitting a 5 month old evry other day....and varying hours..i do not want to seem uneducated to the nice lady who is trusting me with her child..we have a set date to talk but..i just dont know what to ask..im afraid if i ask to much she will think " wow she doesnt know much..i shouldnt trust her.." but if i ask nothing i will not kniow 100% what to do alllll the time...know what i mean..i know the basics diaper changing...games..bottle feeding..but other things... : ) any ideas on how i could approach it..?