When I think of decorating a child's room tropically, I immediately think decorating with palm trees, sand, and mischievous monkeys. A good way to begin this transformation is to go to a local craft store and look at the wall adhesives. Most of the wall-paper like pictures easily stick to the wall, are movable, and leave little or no residue when your child decides he or she wants a change.
If wall adhesives aren't your style, or you want to make the wall a little more three dimensional, then you can take simple acrylic paint and create the palm trees (which are very easy to create for a child).
After the walls are done, find either green bedding or bedding with pictures on it that will mesh well with those that you have chosen for the walls. If you cannot find bedding that you and your child think will work, go to the fabric section and look for the children's fabrics. Usually there will be several tropically themed fabrics to choose from. If you don't want to make the sheets you can always find a solid sheet set that will match well with the fabric you choose for the comforter and then either make the comforter yourself or ask a local seamstress to create the blanket for you. If you have two made one heavy and one light, then you can keep the tropical themed bedding throughout the year.
A good idea for wall art to compliment these decorations, you can either use the previously mentioned wall adhesives or have your child create their own pictures to frame and hang on the walls. If you use one wall as a mural and paint the rest with a solid tropical color your child's wall art will look impressive. Or, you can create a blackboard wall with blackboard paint and your child can continuously draw new wall art.
A tropical vacation wouldn't be complete without watching a sunset or the stars. To create this for your child you can paint a scene on the ceiling, or find star and moon wall adhesives to attach to the ceiling (that way the ceiling scene can be changed out quickly and easily).
There are several periodicals on decorating your child’s room. You can also visit local furniture stores or view online furniture stores. When designing your child’s room, it is important that you keep in mind that eventually your child will out grow his/her room. Try sticking with neutral colors.

Always remember that to make your child happiest with the room, allow them to help in the process. If their shorter, let them help you place art at their height or even, to an extent, paint the mural (there are several easy things that they can do, like paint sand or grass). Take them with you to choose the fabrics and wall art and let them help you decide where things go. They will feel a great sense of pride in the room that they helped create.
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