Stay in your own room as much as possible
Make sure to sleep alone in your room
Use your own tableware
Divide the tableware between you and your housemates. Think about separate cutlery, plates, cups, and glasses.
Use your own towels
Keep your towels and wash cloths separate from those of your housemates.
If possible, use another toilet
If you have multiple bathrooms and toilets in your home, it is smart to use another bathroom or toilet than your housemate. Are you sharing one toilet or bathroom with housemates? Please clean it every day. Making sure there is enough fresh air is also wise. For example, you could open the window for 15 minutes, 3 times per day.