Spray repellents used in a regular basis, find them at your local garden center, follow the directions on the label, rotate the ones you use regularly so the deer don’t get used to them. I like Deer Stopper, Bobbex, and Hinder.
A good, tall, strong fence
A working dog, a Silky Terrier isn’t going to do the trick. You need a lab or a border collie, or a corgi, a real working dog. let them out in the evening and early morning when the deer are on the move.
The one ‘gimmick’ that you find in the catalogs that seems to work is the sensor that sets off a spray of water that frightens the deer.