I've been visiting retailers for many decades. I can count on one hand the number of times I bought something that I wasn't on my "I'll buy one when I find it cheap" list. The subliminal technique that works well on me is a sign that says "buy one get one free" on something similar to what I'd ordinarily buy...assuming that the total price for two is really significantly better than I can get elsewhere on a similar item. I have a bathtub full of breakfast cereal I bought for half-off the normally discounted price.
I do admit that the Victoria's Secret ads on TV have significant subliminal content that makes me want one real hard.