Shape is an important element of design as it helps you achieve achieve better proportion and emphasis for feminine presentation.
Although beauty norms are something we also contest, there are some patterns that are considered attractive for women such as a narrow waist, wide hips and long legs that we can be accentuated using clothing and styling choices. These patterns are gendered cues which we interpret at a glance when seeing a person's silhouette. [1]
Fundamentally, the term “silhouette” in fashion design refers to the line of a dress as well as the outline of clothing or a garment. When it comes to runway, fashion walks, and other similar events, the silhouette is thought of as the first impression of the clothing. Before delving into the specifics of the cloth, texture, etc., it is used to examine the general contour. Making decisions on which body part should be highlighted and which one should be buried is made easier with this information.[2]
In order to get good proportion and balance you should cater your clothes to your body type. There are different classifications of body types people use and even though they are arbitrary and subjective they help set guidelines for those attractive patterns.
2 common types of bodies trans women have (due to aspects of dimorphism) are rectangle and inverted triangle leading us to deal with similar problems like creating the appearance of curves, enhancing the waist and de-emphasizing the shoulders. The following articles provide some tips for addressing this:
https://theconceptwardrobe.com/build-a-wardrobe/how-to-dress-the-rectangle-body-shape
https://theconceptwardrobe.com/build-a-wardrobe/inverted-triangle-body-shape
Another important aesthetic principle is the rule of thirds. Use horizontal breaks in clothing by adjusting the length and height of different garments or by using a belt. This creates a more proportionate look is especially good for emphasizing the length of the legs.
More tips for creating visual breaks with different garments https://hayden-hill.com/blogs/journal/rule-of-thirds-fashion