you don't want to spend time on unimportant tasks, do you? Working on unimportant and not urgent tasks will lead to a bore-out;
working on important but urgent tasks will likely lead to a burn-out;
not urgent yet important tasks are the sweet spot: you work on things matter while still being at the top of your game!
A competent person is capable of taking a complex problem and breaking it down into manageable pieces. There are numerous applications to get organized. I use none of them (save for Google calendar). Of the many systems that I tried, the only thing that I still use daily is (non-artistic) Bullet Journaling. I like that this is an analogue method and only requires a notebook with numbered pages (I swear by Leuchtturm1917). In my simple setup, I have a long-term planner for the next six months, a calendar for the month and a daily log. I use the rapid logging system for tasks, notes and events.
You can enjoy the simplicity of using a simple notebook, or you can apply some sophisticated time management tool, it does not matter. The main point is to regularly take the time to divide your tasks into simpler subtasks and allocate blocks of time to work on them. Whether it is your work, household chores or plain leisure, you always want to ration your scarcest resource wisest.
If most self-improvement books could be summarized into a blog post, then it is only fair that a blogpost on self-improvement can be condensed in a sentence:
Think strategically about your goals, create and follow habits to achieve them and make a plan.
These are the books I found most helpful in organizing my life.
"Straight thinking in the age of information overload", written by neuroscientist Daniel Levitin. The book discusses various strategies on how to organize your home, social life and work.
Cal Newport is a no-nonsense person who practices what he preaches. I can recommend most of his books, especially "So Good They Can't Ignore You". By his own admission it can be summarized as:
do fewer things;
do them better;
know why you do them.
"Atomic Habits" by James Clear is quite instructive in how to tailor your habits to generate excellent outcomes. His weekly newsletter is the only newsletter I enjoy reading in full every time!
A classic and still highly relevant. In summary, the habits are:
(internal) be proactive and take control;
(internal) begin with the end in mind (i.e., work towards a goal);
(internal) put first things first (i.e., make a plan);
(exterior) think win-win (i.e., look at how you can both benefit when working together);
(exterior) seek to understand, then to be understood;
(exterior) synergize (i.e., look how working together can create better outcomes than working separately);
develop good habits to cultivate yourself physically, mentally, socially and spiritually.
You will find echoes of these habits in my own advice.