So throw a nice sweater on or a sports jacket. Don't wear tennis shoes. Dress up the jeans with nice shoes. And you'll have an acceptable, casual but elegant look. The trends that I see right now are any length is in, from mini skirt to full length skirts.
Color again is a big statement, the brighter the better.
And gold is the new silver. But only modified and made simpler and more elegant. As with all colors it really depends on the shade of purple. In other words, the richer, deeper purples. Pastels can work well too, but it really depends on your skin tone.