Neons. Warm-weather leather. Enough black and white to outfit a million Coco Chanel clones. So many trends are buzzing around this spring, a stylista could suffer whiplash. To avoid visits to the fashion emergency room, we suggest a prudent treatment: Dose your closet with a single new item at a time: tropical-print shoes, a lace top, maybe jeans in “it” color mint. “Yes, a few of these ideas can be mixed, say lace shorts with a bright print,” says Julie Egermayer, owner of Adams Morgan’s Violet Boutique. “But the easiest trend? Black and white. It’s something we come around to again and again.” Sort of like spring itself.