Baubles are extremely common decoration, and usually consist of a fairly small hollow glass or plastic sphere coated with a thin metallic layer to make them reflective, and then with a further coating of a thin pigmented polymer in order to provide coloration.

Individuals decorations vary widely, typically being an eclectic mix of family traditions and personal tastes; even a small unattractive ornament, if passed down from a parent or grandparent, may come to carry considerable emotional value and be given pride of place on the tree. Conversely, trees decorated by professional designers for department stores and other institutions will usually have a "theme"; a set of predominant colors, multiple instances of each type of ornament, and larger decorations that may be more complicated to set up correctly. Some churches decorate with Chrismon trees, which use handmade ornaments depicting various Chrismon symbols.

Many people also decorate outdoor trees with food that birds and other wildlife will enjoy, such as garlands made from unsalted popcorn or cranberries, orange halves, and seed-covered sweet cakes.