Menu planning takes a little bit of your time...but it saves you lots of time during your week/month. I plan a month at a time. (One day, I am going to shop once a month - but I'm not there yet.) It usually takes me an hour or two (and a cup or two - or three - of coffee) to get this done.
The first thing to do is to get out your calendar that shows appointments, etc. and a blank calendar for the month in whatever format suits you. I take the blank calendar and mark my husband's shift schedule so I know if he's on days, nights, or off. I plan a leftover night each week based on what he is working. I always cook when he is on days so he has something to take for lunch the next day. (Save money - take leftovers for lunch!)
I choose slow cooker days for those days when I am busiest (Sunday, Tuesday, and Friday). So my calendar works out to Soups on Sunday; Chicken or Pork on Monday; Slow Cooker on Tuesday; Beef on Wednesday; Slow Cooker or Leftovers on Thursday; Slow Cooker on Friday; and Quick & Easy on Saturdays.
Then pick one or two favorite cookbooks and go through them, marking recipes you'd like to try. I take a piece of notebook paper, list the dates down the side, and list the meals I have chosen: main dish, any side/sides, bread along with the name of the cookbook and page number of the recipe(s)for that day. This serves as my master list for grocery shopping. You can make up weekly grocery lists on the day you do your planning and add other stuff you need each week to the premade list.
When I have finalized my menu, I write it or type it on the blank calendar, put it in a plastic sheet protector, and post it on the refrigerator so everyone - including me - knows what is for dinner each night. If something happens and it doesn't quite work out exactly as planned, the world doesn't end. It just helps to have a plan.
I will post my December menu next.