Whether the party is being held indoors or out, here are some ideas for dressing up the space to create a horsey theme. Here are some ideas for decorating the yard to fit a range of budgets and tastes. If you are looking for indoor party decorations we have that too!
OUTDOORS
If you want a simple no-fuss, no-muss decorating scheme, you can dress up the outdoor space with bunches of balloons and crepe streamers. Order some horse-shaped mylar balloons as well. In fact, a horse-themed party pack will usually save you money and time with your decorations!
If you have access to a larger vehicle and if there is a farm, ranch or petting zoo nearby where you can pick up some hay bales, this can be a great way to create a horsey theme outdoors. Range a few bales around the yard to create a ranch-like atmosphere. If you’re able to borrow a saddle or other horse tack, drape it over the bales.
Make hobby-horses and pose them around the yard. Get several lengths of four or five-foot wooden doweling from the hardware store, and cut out horse’s heads from brown, black, tan and white cardboard or craft foam. (You can also go for a “fantasy horse” look and make horses in blue, pink, purple, etc.) Cut twice as many heads as you will need hobby horses. Glue long yarn or crepe-paper “manes” on each head and hide the glued part by sandwiching it between another head. Glue the maned, double-sided horse head around the dowel. Draw on eyes with a Sharpie pen, or buy stick-on googly eyes at the craft store. If you make enough, each guest can take one home with them at the end of the party.

If you have a tree in your yard, make a “horse corral” by hanging horse-shaped mylar balloons from the branches of a tree. (This also works if you have a circular outdoor clothes-dryer!) Or you can hang the balloons in a line along the fence. Choose a color theme for the party (perhaps the birthday girl’s favorite color?) and twine crepe paper in those colors through the fence and around the tree or clothes-dryer.
Finally, a horse-themed party banner is a great way decorate and set the mood. You can even personalize it with the name and age of the birthday girl (or boy)!