Drawing hands can be difficult. It's best to see it as a shape and not be too involved with depicting all the fingers. Think of it as a mitten. Always illustrate the thumb and at least one finger.
When drawing feet, think of them as hooves. A foot in a high heel is very similar in appearance to a calve's foot where the toe is the nail of the hoof and the heel of the shoe is the ankle joint of the hoof.
In drawing hands and feet, practice at least three different positions to memory and just repeat them over and over. There is no rule stating that you have to be a great hand and foot illustrator to make a beautiful full-body fashion illustration.