You don't need bait to kill sika deer. You just need to hunt them. They aren't so different than white tails, its just the cover is different than what you are used to. You can pattern them like any other critter. They aren't quite as predictable but if you learn what they like, its not difficult to put yourself in high probability spots. A lot of sikas are killed at Blackwater, Fishing Bay WMA and other areas open to the public where baiting is illegal (wish it was everywhere). I hunt private land where we don't bait. It's a lot more fun hunting deer that act like deer and not drooling pavlovian robots coming to a pile of corn.
As far as leaving trails, they are creatures of habit and leave lots of evidence of their preferred routes. Get on google earth and zoom in on the marsh/woodline edges and you will be able to see trails that will make you drool. The biggest problem is figuring out which ones to set on.
They are a great hunt if you are willing to work for it. Come the week of Columbus day and you should hit the rut and I can promise you you won't find a more exciting hunt. Hip boots, thermocell and GPS are critical equipment.