First of all, you have to know that nails are not tools. So don’t use them to open cans, scrub, press buttons (especially the bathroom or the bus), etc.
It’s also important to wear gloves when washing dishes or doing cleaning tasks that require putting your hands in the water, to take care of the work a little more.
If the client likes to eat their nails, their most important task is to stop taking their hands to the mouth, because as much as the material is resistant, is not foolproof.