Clothing is hard to draw as it has a number of odd folds and wrinkles. It can take random shapes depending on the form on which it falls. So, a few factors are to be kept in your mind while drawing clothes.
The material of clothing: Thicker material and thinner materials results in lesser folds and more folds respectively. Stiff material clothing would have triangular folds, whereas softer material produces rounded folds.
Cut and fitting of clothing: Loose fitting clothes are influenced by gravity. Tight cut clothes, however, wrap around the form.
Movement of the subject: When in rest, the shape of drapes depends on gravity. But during motion, folds are influenced by the direction of the force and external factors like wind and rain.
Pulling point, or point of tension: Folds are mainly formed due to points of tension. These are mostly joints of the human body, like shoulders, elbows, knees among others.
Shadows and highlights: Depending on the direction of light and the type of material, the reflection of light varies. Smoother clothes have brighter highlights.
Follow the above steps to visualize the cloth folds and wrinkles in your imagination and give life to them.
