Preparing before you hire a live-in housekeeper can make their job and your life easier at the same time. In fact, getting ready for a new member of your domestic staff may help you start a good relationship with them, as you'll already have the products they need to get started.
There are multiple reasons to do this. Even experienced professionals might not know what you prefer to use on your floors; and rather than simply telling them, you could have the specific cleaning materials ready for them to use, so they know what to get next time.
Having the products ready also might be something your incoming staff wants from you but can't tell you directly: A Reader's Digest article about the things home cleaning staff think about said that having the right products ready makes the cleaner's job easier. This is true not just for soaps and solutions, but important tools like mops as well.
Thinking ahead about cleaning also means considering long-term impacts. You might, for example, want to use organic or "green cleaners" in your home. However, a Live Science article said that some products could require more effort to have the desired effect in and around the home during cleaning. You may not be doing the cleaning yourself, but this could still slow down your staff over time, so prepare for this accordingly.
All of this may make it sound like you have to do extra work even after hiring help. In reality, the little preparations you take could ultimately lead to a better experience and make it easier to clean your home. Good communication will also make you more comfortable giving new and different instructions to your housekeeper as your needs change over time.