It nest base the the rectangular area of the image/object. To minimize vinyl usage, i recommend manually positioning the items in whatever vector program you're using.
I used to do this all the time in corel for banners. After completing the design, I'd duplicate the whole thing and break it apart by color, with each color in a 22" max height row (was using 24" rolls.). This also allows you to do some trade off by making decisions where ease of application is more critical and using minimal vinyl.