Such training for the skin may be secured by various means. One should first accustom himself to a gentle draft. Cool bathing, to a point that produces a healthy reaction, is another important feature of skin training. Cold bathing, by those affected with kidney trouble, is not advisable, but delicate individuals, who cannot react well to the cold bath, can greatly increase their resistance by graduated cool bathing performed as follows: Standing in about a foot of hot water, one may rub the body briskly with a wash cloth wrung out of water at about 80 degrees F. and reduced day by day until it is down to 50 degrees F. Following this the cold douche or affusion may be taken (water quickly dashed from a pitcher) beginning at 90 degrees F. and daily reducing until 50 degrees F. is reached, or just before the point where an agreeable reaction ceases to follow. [Sidenote: Light Clothing] The wearing of loose, porous clothing, and the air bath--exercise in a cool room without clothing--are also valuable measures in skin training. Very heavy wraps and fur coats should be worn only during unusual exposure, as in driving or motoring. Outer clothing should be adapted to the changes in the weather, and medium-weight underclothing worn throughout the winter season. Office-workers and others employed indoors are, during the greater part of the day, living in a summer temperature. The wearing of heavy underclothing under such conditions is debilitating to the skin and impairs the resisting power. Overheated rooms should also be avoided for the same reason. In rooms where people are moving about, the temperature should not be allowed to rise above 65 degrees. In ordinary offices or dwelling rooms, the temperature should not be allowed to rise above 68 degrees and adequate ventilation should be provided. [Sidenote: Fresh Air] Living out of doors, especially sleeping out, gives the skin exercise, and further keeps fresh air in the lungs. It is one of the foremost methods of prevention against colds. Army men remark that so long as they are out of doors, even if exposed to bad weather, they almost never catch cold, but do so often as soon as they resume living in houses. Long breaths taken slowly and rhythmically, say ten at a time and ten times a day are helpful. [Sidenote: Constipation] Constipation predisposes to colds, and should be vigorously combated by proper diet and exercise, and regular habits of attention to the bowel function. [Sidenote: Overeating] Overeating frequently leads to nasal congestion. Eat lightly, using little meat or other high protein foods such as white of eggs, and thoroughly masticate the food. [Sidenote: Fatigue] Avoiding undue fatigue will help greatly in preventing colds. [Sidenote: Nasal Toilet]