Foxtrot is actually my favorite dance to choreograph. Of the smooth dances, it is by far the most playful, with no shortage of opportunities to "tell a story" and show the relationship between man and woman. Think of every MGM movie you've ever seen with Fred Astaire & Ginger Rogers.
If you really want to get an idea of what people are dancing these days in Foxtrot routines, pick up a copy of the US Ballroom Championships (American Smooth division) from dancevision.com. Or better yet, just reach into your closet and fish out one of the old Fred & Ginger movies.
You can also borrow moves from other dances such as Waltz & Tango, or even open work from the Latin dances (I just borrowed a Mambo step for one of our weekly variations last month -- worked great in Foxtrot). For open & side-by-side choreography, you can use any number of jazz movements such as grapevines, step-points, jazz boxes, twist-turns and a variety of spins.
Good luck!
Sincerely,
Jonathan Atkinson
www.ballroomdancers.com