There are many options for decorating a unisex room for a boy and a girl. You can use solid colours and choose a theme that both of the kids like. If the children are old enough to decide on the theme themselves, ask them how they want their room to be decorated and discuss it until they come to an agreement. As a last resort, decorating with a solid colour is a safe way to go.
There are many different animal themes that you can choose from to decorate a room. Jungle and rainforest themes work well because the animals who live there are exotic and not associated with either gender. Paint a mural on the walls that has monkeys, elephants, gazelles and parrots. You also can paint a canopy of trees and butterflies. If you do not want to paint a mural you can use these themes in the border and with your bedding and accent choices.
A nautical theme is great for a shared bedroom due to the variety of decorating choices, according to the Decorating Kids Rooms website. For example, you can hang a fishnet on the wall and add various items to it like starfish and seahorses. Also, decorate with patterns that feature an anchor. Use decorative accents like filling glass jars with sand and seashells. Decorating Kids Rooms recommends that you create bookends out of oversized seashells. Use colours like cream, navy blue, and red with this decor.
Use a solid, neutral colour to decorate the room. Paint the walls one colour or use varying shades and stripes or large one to two foot squares along the wall. This will provide a dominant colour and keep the theme together. Stay away from decor that is gender specific, like princesses or cars. Instead, accent with primary colours or others that work with your dominant colour.
Make sure you have enough storage in the children's room. Create space that is specific to each child. This will give each of them a space of their own to put toys and other belongings. These storage units should be secured to the wall and easy for the children to access, so that it will not pose a safety hazard.