If you happen to have a couple or more glass jars around, you can recycle them and use them as storage for small stuff in your bathroom. You can mount them on the wall and place your make up brush, q tips, etc.
Organize your bathroom vanity by putting toiletry storage. Choose a multi-tier storage or a candy dish and place all your bathroom essentials accordingly.
Use the backside of your bathroom door and hang dried towels. Arrange the hangers on top of each other and label them with names of their owners.