Never know what we are going to have a week in advance. I make sure that there are staples in the freezer that we can defrost if we want them - pasta sauces, chilli, curry, fresh pasta, minced meat, stewing steak, fish - to either reheat or use to make whatever we fancy.
Our main shop (about once every three weeks) is almost the same each time, just a few different things added like kippers, or smoked haddock to make kedgeree, or a particular cheese we fancy. Once a week we add in more fresh veg and fruit, bread, and anything else we might want.
Very little gets wasted - lots gets made into meals/sauces/soups and frozen.