Twilight’s Ashley Greene might have looked red-hot at last night’s L.A. premiere of the film series’ latest installment, New Moon, but she tells PEOPLE that finding her perfect scarlet Prabal Gurung stunner was no small matter. “We picked a dress out, had it ready,” Ashley says of a different look, which she originally chose with her stylist. But at the last minute, “I decided I didn’t like it and we had to start from scratch.” Just how down to the wire did it get? “I stopped by the tailors right before I got here to pick up the dress,” she admits. The rest of her red-carpet prep, however, was less of an ordeal. For two hours on the Sunday before the premiere, Ashley received eyelash extensions from expert Calma Yom at The Parlour on 3rd and then returned to the salon to have her hair extensions freshened up the following day. As for her bronzed skin, Ashley looked to St. Tropez tanning expert Fiona Locke, who customized and contoured her skin before the big event. The final touch came at the hands of makeup artist Vanessa Scali, who created the ’60s-inspired look for the the Twilight star with “well-defined eyes with lots of lashes, a strong brow and clean skin with subtle pink [and] coral cheeks and lips.” additional reporting by Lisa Ingrassia