Do you use a planner?

Paper or computer based?

Part of my endless array of courses and workshops I am taking, I just went through one about "time management", and I was wondering if other people plan their day/week/month and so on. In detail, or more loosely? Do you stick to do what you planned,  or do you mix and match, and do whatever feels "right" at  the time?

If you do plan your days, do you have any insight and advice for someone that is new to the idea?

I use a daily checklist app and make sure I have everything done on it each day.
Not only does it help me get things done, it also makes sure that I don't do something twice!

I've found that a regimented/strict schedule tends to stress me out if I miss one part of it, so I've stayed away from those.

I signed the GrowVeg planner for one year and by now it seems to be worth the money.
It has a lot of features where I entered the Veggies. trees, buildings and garden features (if they are not on the list you can edit one) and you can enter the time where they will occupy the grow beds.
When the first harvests are done you can correct these times accordingly and make notes about anything you want to remember.
It has also companion planting features and gives you info which crop should not be following up in the same grow bed.
Beside this the time planner is useful and can adjusted by yourself and it will give you the weather forecast almost at your location.

For a market garden it is sure a good tool that supports the farmer keeping track but it might be for a single grow bed owner a bit of an overkill if you not use it for your entire backyard incl. trees and buildings.....

Fridge calendar works pretty well for us.

I use a paper planner in addition to a shared Google calendar with hubs. I don't always stick to it and don't beat myself up if don't tick all the chores/tasks, but it does help me to keep things straight. For things that occur on a set schedule like changing the fridge filter or something I set a reoccurring calendar event in my G-calendar to notify me. I've found that adding tasks that might otherwise get forgotten about are many of the things I add, like something that should be regularly deep cleaned (that really should be done more more frequently than once a year or decade).