Meet my beautiful friend Sarah. Sarah commissioned me to do a custom illustration of her in her wedding gown. (I didn't know her at the time of her wedding otherwise I would have offered one as my wedding gift, as I do for all my friends who are about to head down the aisle!) Sarah is an Orthodox Jew and therefore her wedding gown was modest, with a high neckline and long sleeves. This was out of my "bridal drawing comfort zone". 
Drawing a bride is hard because they wear intricately detailed white gowns that I have to draw on white paper. Usually all the skin shown with a strapless gown helps to give the illustration depth and a frame of sorts around the dress, so this one obviously didn't have that. Also, knowing Sarah, she is such a beautiful girl, both inside and out and one of the most kind hearted people I've ever met. I wanted to really capture her in my illustration. (cheesy I know, but its true!) But I'm really pleased with the outcome and so was Sarah.
The first step in tackling any fashion illustration is to choose a pose. Looking at a picture is the best way to do this. It takes some time to find good poses, so you should hold onto them and start a "pose" folder for future reference. I've found that be best resources for tears are high fashion magazine editorials and catalogues. Bathing suit layouts are great because the figure is not hidden under clothing.
The most important element to look for when choosing a picture is that the top of the head to the tip of the toes be visible. It must be a full body shot otherwise your just guessing what the legs or feet look like and your drawing can come out distorted if your guess is not accurate. In the beginning its also best to choose poses that are straight forward, with the head and body facing front. Three quarter poses and profiles can get tricky.
To begin drawing a pose from a photo it's helpful to make a copy of it (or place tracing paper over it) and draw the shoulder, bust, waist and hip lines as well as the center line and panty line, as I have done with all these images. (This helps to know where seams and other clothing details should be placed.) Then draw a loose gesture drawing to get the main muscle masses down. You can create the final sketch outline from the gesture drawing and erase the unnecessary inner lines or just layer on another piece of tracing paper or thin marker paper and outline the body. Then start designing! 
