The most visually-striking aspects of an artificial flower arrangement are the petals’ colors and shapes. There are, however, many more considerations (than simply the petals) that contribute to the appeal of a well-styled bouquet. The more technical details, like number of stems, height of stems, number of leaves, the amount of space between each stem, and the way the stems fall or bend, may not be as noticeable as shape and color, but do play key roles in creating the perfect aesthetic. Before you think about the more visual elements, make a checklist for sizing. Think about how tall you want the arrangement to look (consider the height of the vase), how wide the overall bouquet should span and how sparse or dense of a feel you’re going for.
It goes without saying that the taller your vase, the taller your stems should be. Make sure all blooms peek over the edge of the vase. (How high the stems should be over the top will depend on the amount of stems/flowers; very tall, elongated stems that rise ten or more inches over the top of a vase look best in sparse arrangements of no more than two or three flowers, but shorter stems in which the blooms sit just above the edge of the vase look best in dense arrangements of nine flowers or more.)