Start with a centerpiece.
Make or purchase an appropriate autumn-themed or Thanksgiving centerpiece. Use a traditional cornucopia centerpiece or an autumn floral arrangement. Scatter fall leaves and nuts around your centerpiece. Keep your centerpiece small if your table space is limited.
Add candles and seasonal items.
Use autumn-colored candles set in wooden or rustic metal candleholders to decorate your table and to use as a centerpiece. Arrange fall foliage, wheat sprigs, clusters of berries, nuts, and mini pumpkins and other seasonal vegetables around the base. Keep candles and arrangemens at a height that will allow diners an unobstructed view of each other.
Use a pumpkin for a vase.
Use a large, hollowed-out pumpkin instead of a vase to display a fall floral centerpiece. Scatter sprigs of wheat, clusters of berries, nuts and autumn leaves around the base of the pumpkin.
Dress your table for autumn.
Set your table with a tablecloth, table runner, place mats and napkins done in autumn-themed prints and coordinating solids. Use prints sparingly to avoid giving your table a "busy" look and to keep attention focused on your centerpiece.
Accessorize with napkin rings.
Use napkin rings that reflect the season as well. Hand-paint leaves onto plain wooden napkin rings or use purchased napkin rings that have a similar motif.
Bring out the “good” dishes.
Use your good china or dishes done in autumn motifs and/or colors that coordinate with the colors used in other elements of your table's decoration.
Bring nature indoors.
Use clean autumn leaves as place cards. Rinse leaves and pat dry. Write each guest's name on a leaf with a black or gold felt-tip pen. Place one leaf in the center of each plate.