A very thorough set of courses on Fashion Illustration
Using Croquis figures
https://www.youtube.com/watch?v=gX7uFHshHDk
Drawing figures: shapes and proportions
https://www.youtube.com/watch?v=XzD60RfgdfE
Drawing figures: fleshing it out
https://www.youtube.com/watch?v=YuW402qMU3Y
Different approaches: men and women
https://www.youtube.com/watch?v=JZxuGne2FIk
Female figures female
https://www.youtube.com/watch?v=HEqaB-657f8
Male figures
https://www.youtube.com/watch?v=OG5rnyhYAaI
Side figures: male
https://www.youtube.com/watch?v=3TpeMifEQ3U
Front view faces
https://www.youtube.com/watch?v=WeLjcJgR7zY
Different angles
https://www.youtube.com/watch?v=ZuCDa7e7o4s
Multiple media
https://www.youtube.com/watch?v=k8Av7rVhoxQ
Hair
https://www.youtube.com/watch?v=oOSSefUjNrU
Hair: colour pencils
https://www.youtube.com/watch?v=LCFb2TA7TCc
Different styles
https://www.youtube.com/watch?v=_H-wOr3XEHg
Media
Paints
https://www.youtube.com/watch?v=YhdA2sNw6n8
Fabric
https://www.youtube.com/watch?v=3yh2uapUw0k
Clothes
Wrap arounds
https://www.youtube.com/watch?v=JuSewX0F3Zg
Drapes and Folds