I'm returning to work so we have fairly recently employed a nanny/housekeeper 2 days per week. She has set hours when she looks after the children and set hours when she cleans the house. She does the same role for another family 3 days per week.
She is absolutely lovely, the kids like her, she seems trustworthy and responsible. She is just not a great cleaner! We really wanted someone who could help in the house (put washing away, tidy toys, change beds, pack nursery stuff, etc) rather than simply cleaners. She's quite good at that stuff, but she isn't good at the actual basic cleaning. Yesterday I had to wash the floors and clean the bathrooms after she'd left. Everywhere was sort of vaguely cleaner than when I left but nowhere near clean enough. She was allocated 6 hours of cleaning (Thursday is her main 'cleaning' day) which should be enough!
Anyway, how do I go about trying to get her to improve her cleaning? I have a list we wrote together for her to follow for each room but she clearly isn't following it.
I am a very shy, non-confrontational person and for good reason I don't have management responsibilities at work (of people, at least) I'm just not sure how to approach things. Do you have any good tips or phrases? I don't want to seem critical. Even though I am 
I'm really keen to keep her, she's lovely and it's taken us ages to find someone suitable as we live in a small town so there are very few candidates!
Any advice from more seasoned nanny/housekeeper employers?