Use the sale fliers. I try to stick to the meats, fruits and veggies that are on special and plan my menus around them.
I also save by using grocery store brand frozen berries and veggies. They taste just as good as the brand name things but are less expensive.
Saving $ on those things makes it easier for me to splurge on the things I rarely find on sale, like my sprouted grain breads and almond butter, etc.