Focus on adequate protein and fat, with relatively low carbohydrates, and short, intense exercise to stimulate muscle retention (hmmm . . . sounds a lot like "Zone + CrossFit", what a surprise!!)
Seriously, that's about the best advice I can give, other than to note that it will probably take longer than you want. If you want to avoid losing any muscle, I think it will very hard to lose more than 1/2 to 1 pound of fat / week.
Standard advice for anyone looking to improve their diet . . . eliminate all the "junk" carbohydrates . . . cake, cookies, soda pop, pasta, rice cakes, most bread (some would say all bread) and flour products, most or all alcohol.
If you want faster results, cut calories more . . . but understand that you'll probably lose some muscle along with the fat.