Decorating a child's room can be a never-ending process if you are not careful. Trends, characters, and icons are ever changing and so are kids' tastes. There is no guarantee that your child will like the same thing in a week, a month, or even a year so it is best to shy away from fads and stick with universal decorations.
Styles and themes can vary without being specific. Choosing characters like Hannah Montana, The Incredible Hulk, The Wiggles, or Mary Kate and Ashley can turn into trouble in the long run. Instead of picking specific items such as Cinderella pick the broader category of princesses in general. Children grow out of things and this should be taken into consideration.
There are a lot of great decorative ideas that can be suited for kids of all ages. Pick teddy bears, clouds, kittens, smiley faces, American themed (stars, stripes, and flags), celestial, hearts, flowers, religious themes, or horses. Basic decorations are best for shifty kids. This way, you don't have to spend a lot of money redecorating every time a new icon comes out.
Talk to your child about their favorite hobbies in a general sense and try to come up with a theme that will best suit their taste. Go shopping together for fun items that will look good covering the space in their room. Get your child involved (if they are old enough) in the process from beginning to end and they will be more sentimental about the way it turns out rather than insisting it be changed.
Pick a paint color that is happy and cheerful but will go with the chosen theme. White is a good color but gets dirty easy. Black is a drab color that should also be avoided. Choose shades of light blue, pink, yellow, orange, red, or green. Some home improvement stores will even let you custom mix your own color.
Once the wall is painted add other decorations. Choose wallpaper borders in the theme you chose. Traditionally border goes across the top of the wall touching the ceiling. This is good for a classic touch but doesn't look as great in a child's room. Opt for running the border around the middle of the room, eye level for the child.
If you are artistic, you can freehand pictures or words on your child's walls. If you would prefer to, you can use stencils or sponges to add details. You may even want to decoupage (cut and paste items collage style) some pictures in different spots.
Choose curtains or simple blinds that will pull everything together. Screen style blinds can even be decorated to match the walls. Match carpet and rugs to the window coverings. Just as you did with the walls, shy away from white and colors that can be easily dirtied up.
Remember that ceilings can be functional for decorations also. Swirl paint up there, cover it with posters, or personalize it with your child's name. You can also go with the classic celestial or outer-space theme. Attach glow in the dark planets, stars, rocket ships and other fun items that can be found above our heads.
Match the bedding to the rest of the room. You can even add stickers or decorations to the headboard. This also goes for small child size furniture or tables and desks. Pick items that will be comfortable for your child but will still look good when combined with everything else.
If your child has a lot of stuffed animals or dolls use netting to hold them. Secure the net to the ceiling and place all the soft creatures inside. Arrange them so that they can be seen individually or appear to be looking down and watching over the child.
Because children often accumulate a lot of items, storage space and organization is important. Fasten shelves on walls for collectable items that the child doesn't play with such as porcelain dolls or die-cast cars and trucks. You can also affix bookshelves on the walls but should place them low enough that the child can easily access them when they feel the need to read.
For thrifty solutions you can use stackable crates or plastic storage containers to store toys. Use old diaper wipe containers for small toys or crayons and markers. Disposable laundry bags will hold balls, sports equipment, and outdoor toys. Slip the bag on a hook on the back of the door so that they can be grabbed in a hurry. Separate items so that they are easier to find when your child is searching for them. Label containers for easy pick-up.
If your child's room has a closet, customize it for maximum storage space. Slide your child's dresser in the closet so that it is out of way but still functional. Use overhead closet shelves for storage. Hang shoe racks/bags on the inside of the closet door so that they are together and up off of the floor.
The most important thing of all, perhaps, is the space factor. Regardless of the style you have choose your child's room still needs to be functional in the sense that it is their personal space. Try to put items against the wall rather than in the middle of the floor. Leave plenty of room for your child to move around and play. It doesn't matter how pretty the room is if the child can't move around and enjoy it.
No matter what you choose put a little thought into it. You are free to change things at any time but this can be time consuming and expensive. Children love new things and a change of pace so chances are that no matter what you do they will love it. If your child is happy, that's all that matters.