I think that using todo lists is bad and that you should stop doing it. I think a better idea is to book time in your calendar to complete your tasks. I got this idea from Wolfgang Reck when I took his workshop (provided through my employer):
https://otc-int.com/index.php/time-power-management-workshop-pmw-1/
The goal of the todo list is for you to complete your tasks. Tasks need to be completed using your time. A task without a time allocation is in an unnecessarily incomplete state. There’s no possible way for it to get done without allocating some of your time. There’s no reason to procrastinate the task of allocating time by putting it on a todo list. Book time in your calendar to complete the task once you decide it’s something that needs to get done.
Having an item on a todo list leaves questions unanswered. Will I get the task done tomorrow? This week? Before a relevant deadline? Which task on the list should I do first? If someone asks me to take on an additional task, will I have time? All of these unanswered questions can nag at you and cause unnecessary stress. Booking tasks into your calendar forces you to have an answer to those questions upfront. Delegate the mental load of time allocation to your calendar.
Todo list helps with the error of failing a task because you forgot about it. It doesn’t help with the error of failing a task because you remembered it, but didn’t prepare properly.
Another related problem with todo lists is when people put vague items on the list, without fully considering how much time will go into that item. For example, imagine I have an exam that I have to pass for my career. Putting “study for exam” on a todo list is a lazy, bad approach to solving the problem. It’s ignoring a big component of the problem (time allocation) and hoping it will work itself out.
The first step in booking “study for exam” into my calendar is breaking the task into components. For example, I might have three one-hour chapters to read. And one hour of practice questions for each chapter. I can book six one-hour (or three two-hour) sessions in my calendar to tackle the chapters+questions. I could also book a review session, if necessary.
Even if I study and take the exam, I might still fail. If I fail, how much time will I need to study again and retake the exam? If I want 14 days to “re-study” after a failure, I need to make sure to book my original exam at least 14 days out from the deadline. And to have time booked in my calendar after my exam date for studying (those sessions can be canceled if I pass on my first attempt).
I can even schedule a safety factor into my schedule. If I think each chapter will take one hour to read, I can book two hours. Or I can have a block of time in my calendar reserved for “emergency study”. Activities that take longer than their expected time can “spillover” into the emergency session.
One problem with scheduling tasks is that it takes time. I can’t book sessions into my calendar while meeting with a client. Or walking home from the store. Keeping a short term list of items that need to be scheduled is okay, as long as you schedule them asap. And then throw out the todo list.
Besides a general todo list for things you want to do, you can have more specific todo lists. You might have a todo list for work tasks, which you only check while at work. You might have a todo list for sub-tasks within one task, which you only check while working on that task.
I think this is still ignoring the problem of time allocation.
Also, I don’t think sorting tasks by if you want to do them is a good idea. I think a task either has to be completed (in my opinion) or it doesn’t. If it has to be completed, then I have to do it now or put it in my calendar. If it doesn’t have to be completed, then I ask if I would ever want to do it during my spare time. If yes, then I put the item on my “later” list. I do items from my “later” list when my schedule isn’t booked.
I think that covers things I want to do, but don’t consider necessary. Stuff like trying a new video game, going for a hike in a specific park, reading a particular book, learning a new work related skill, etc.