If you have them, little red wagons, and train sets look wonderful under the tree. Spray on window snow doesn't cost much and is a nice touch . Take the time to plan a design. Cut out stencils before you spray. As an alternative, cut snowflakes out of white paper and put them on your windows.
Stockings always look good , no matter how simple.
Try and display them prominently. Wreaths exude warmth. I've made them through the years in everything from just yarn to flowers. Look for inexpensive wreaths at Goodwill type stores. You can add your own touches to them to make them look better.