To complete a costume and be really well dressed, a becoming hat is a must - and the woman doesn't exist who hasn't felt her spirits rise when she wears a becoming new hat.

A hat is properly worn in church, at luncheons, teas, on trains, ships and airplanes. A hat should always be worn when going into the city or a place of business. A rule of etiquette is that hats are worn and left on at all functions before six o'clock. I cherish this rule. It reflects gentility and good taste, and shows respect for your hostess. Any outfit will be enhanced with the addition of a beautiful hat.

Don'ts:

Don't underestimate the importance of a hat. Without a hat, a street costume is incomplete. Without a hat, you miss your full share of beauty,

Don't choose a wide-brimmed or drooping hat if your neck is short and thick. Be sure that the one you wear shows off every inch of your neck.

Don't try to find one hat to go with every outfit when choosing a hat. You end with a hat that goes with nothing.

Don't match the fabric of your hat with that of your suit. Another color or texture may be more flattering to your face and hair.

Don't if you have a large face and ample figure, pick a fairly bulky hat with upward lines.

Don't wear a hat with soiled band, veil or flowers. Replace them with new ones. Remember, too, how fresh a veil looks after pressing under waxed paper.

Don't wear hats with high crowns or vertical lines if you are tall.

Don't get in a rut and wear the same type of hat year in and year out. Wear several different shapes and variety in color, fabric and trimmings.

Don't repeat a bad line. For example, don't let the brim of a hat follow the line of a too large nose or repeat the upturn of a too tilted nose. An irregular brim or soft trimming that projects a little over the forehead is always helpful in either case.

Do's:

Do avoid center trimming if your nose is no asset. The eye takes in the feature you would prefer to minimize.

Do be sure that your hat is as wide as the widest part of your face. Otherwise, your face will bulge out underneath it, and any defect of contour or feature will be exaggerated.

Do, if you wear glasses, keep in mind that your hat should show most of your forehead.

Do wear hats of soft lines and fabrics for their effect on angular features and contours. Avoid anything hard or sharp - it will make your face seem severe.

Do choose an eye veil instead of a full one if you would like to look younger. It's less matronly.

Finally, never underestimate the power of a well-chosen hat to enhance your beauty.