So at some point, I switched from my task list to my Gooogle Calendar – a step that I'm still very happy about, as it skyrocketed my performance (both real performance + felt productivity).
Here is how this works for me right now (still tweaking the system sometimes):
Whenever there is something coming up, or somebody asks me to do XYZ for them, I need to find an appropriate time slot in my calendar and assign it properly.
The calendar, at the same time, is combined with Calendly, the solution I use so that clients and people interested in working with me can use to book time with me.
From a private point of view, it's also been a win: whenever my wife has an appointment, a business call or whatever, she notes it in her calendar which gets synchronized with mine – so I always know ahead of time when I'll need to be at home with my kids and won't be able to attend any calls.
In case you're facing a similar situation like I did, with tasks accumulating on your task list without proper organization, I'd highly suggest you give it a try: moving all you have to do to your calendar within your working hours forces you to assign time slots in a realistic way – at least for me and my productivity, this move did wonders.