Where can one learn how to do a fashion sketch?

Fashion sketches or drawing skills in general are skills which requires frequent practice. When a person draw, the techniques and styles develops and improve. There are life art classes, which one can consider to take, it can help artists to get an idea of the anatomy. In the fashion industry there are often sketches of people wearing the clothes. Other than life art classes, there are some educational institutes that offer courses like fashion and textiles or design technology, which could help develop drawing skills and fashion sketches to build a portfolio for higher education.