Use the adjective over-the-top to describe something that's excessive or exaggerated, like the over-the-top birthday party your uncle threw for his two year-old, complete with ponies, clowns, and a chocolate fountain.
When something goes way beyond what's expected, it's over-the-top. Your sister's outfit can be described as over-the-top if she is wearing a sequinned dress, a feather boa, and a black silk top hat. The gift you give your fourth grade teacher is also over-the-top if it's two tickets to a Broadway play and a diamond ring. When something's over-the-top, it's a little outrageous.