Good fit is so important to the success of your designs. To get it right, the fit for each design needs to be tested and tweaked on a fit model during the development process. Your fit model represents your customer and is specific to your brand.
A fit model is different than a runway or photo model. Traditionally, these types of models are tall, thin, and aspirational. A fit model, on the other hand, needs to represent the size, height, and shape of your actual average customer. If you are designing clothes for tall, thin women, then your fit model should be tall and thin. If you are designing clothes for athletes, your fit model should be an athlete. If you are designing clothes for petite, full-busted women, your fit model should be petite and full-busted. You get the idea. Your designs will be made to fit your fit model perfectly in hopes that they will then fit the rest of your customers as well.
Your fit model should be a woman who wears the middle size in your size range (which should be your sample or base size). If you are running sizes XS-XL, your fit model should be a size medium. Again, you want your fit model to represent your average customer. Fitting your middle size will also help your sizing stay more consistent as you only have to go up a few and down a few sizes to get all the sizes in your range.
If you are expanding your size range or are launching your first collection, you may also want to fit your designs in other sizes as well once the middle size is approved. These fit models should represent your average customer that wears that size. This will help you confirm that the size grading fits your target market. Once your grading is confirmed, though, it isn’t necessary to fit each design in multiple sizes during development.
I’ve talked before about the benefits of fitting on a live person. Don’t just fit on a size medium dress form and call that good enough. Find an actual woman who represents your average customer and have her come to each fitting to try on your designs. She will be able to provide feedback on how the design feels, how it moves, and how easy or hard it is to put on that a dress form can’t give you.
In addition to your fit model being the size and physical shape that represents your actual customer, it is great if she is also part of your target market in other ways. If she likes the style of your brand and shops within the same price points, she can also provide feedback on what she would pay for your design, how she would wear it or style it, and what design features she appreciates. This type of feedback goes beyond just fit, but it can be a valuable way to see how your average customer might react to your design and what features she finds valuable.
In summary, your fit model should represent your average customer in size, shape, and target market. She will try on your designs throughout development so you can see how they will fit the end customer.