If you are planning shelves for storage in your new bathroom, consider building shelves that are recessed into the wall. These shelves can be either framed with trim or left unframed. Or you can add doors to keep things on the shelves dust free. In a small bathroom, doors with glass or frosted glass doors will make the room appear more spacious than solid wood doors (and frosting creates enough blurring that you don’t need to be quite as neat). You can use the shelves strictly for storage or you can mix storage and display of decorative items. If you cannot or do not want to build recessed shelves, you might consider installing glass shelves. Because they are clear and reflect light, they do not make the room look smaller, as wood shelves might do.
In a small bathroom, less is always more. If you include a vanity, you will probably need to choose a very small unit. Depending on your needs, you can choose the style (cabinet or drawers or a combination) that is most suited to your needs. Recessed medicine cabinets (set into the wall, with an unframed mirror) are ideal in small bathrooms.