I easily get stressed so many years ago, I made myself a commitment to get organised and stay organised. So I'm on top of everything, all the time, really. It's such a comfort to know that I've literally got nothing outstanding or overdue, whether business nor personal. My work at that time had sent me on a "time management" course as I'd clearly been struggling at work juggling a portfolio of a few dozen clients with differing needs and priorities.
I expected the usual platitudes, and list writing hacks, prioritising hints and tips, etc., as I'd been on similar courses previously, but this one was completely different. It was all about "just do it" and advocating a one touch approach (it was paper back then, but equally applies to emails etc).
Basically, when you get your post in the morning (or today it's your email in box), you look at everything, but only once. You decide at first glance whether it's something that needs your attention at all. If not, you shred it/delete it and forget it, whether it's a business letter, bill, quotation, professional magazine/leaflet, etc. He told us to be honest with ourselves and if we genuinely were going to do nothing with it, then just get rid and never look at it again. Even if it was, say, a reminder for a bill - if you couldn't pay it there and then, shred it as they'd send another reminder later. It was ALL about decluttering your desk, in tray, mind, etc. Use the 80-20 rule, to get rid of the useless clutter, the 80% and that leaves you with a manageable pile, 20%.
Once you've done that, spend the rest of the time dealing the 20% that actually needs dealing with and that you can deal with.
It revolutionised my working life. Obviously it took time to clear my backlog, but I stopped it growing by prioritising stuff that "came in" day by day, and what was left of my time I spent clearing the backlog. It was a lovely warm feeling to see the backlog shrinking. Far better than ignoring new stuff coming in, and concentrating on old stuff, where you knew you're backlog was never shrinking. Constantly writing and re-writing to do lists and prioritising stuff takes up a huge amount of time. Far better to spend the time actually doing the work, rather than writing about it!
Because my working life improved so much, I applied it to home life too. Whether household bills, home improvements, DIY, cleaning, laundry, cooking, "life admin", son's school affairs, etc. Whatever needed doing, I just got on and did, there and then. I stopped letting laundry pile up and doing several loads at once and started doing it every day or two - much easier to iron a dozen items rather than it piling up to have to 50! Better to sign son's school form or send a BACS payment for something as soon as the paper slip arrived, rather than trying to remember doing it later.
It just clears your mind when you've literally nothing to remember, nothing preying on your mind that needs doing, etc. I've got our wills sorted, POAs, instructions for our funerals, a file of all "big" stuff to do with the house for when it gets sold, i.e. initial purchase solicitors paperwork, estate agents brochure, survey and searches, planning permissions, bills and guarantees for all work we've had done, etc - all in one place to make it easier for when we (or our son) come to sell the house. Same with personal finances, got all our ducks in order (i.e. instead of various bank accounts, pensions etc in different places, we've streamlined it all so it's easy for each other and son to follow and know what's what). Bills all on D/D out of a joint account, so again we both know what's going on and when one of us dies, it will all seamlessly carry on with it being a joint account.
My work/business is just as organised. As I walked through the office door this morning, I literally had a clear "to do" list, nothing to do, etc. An hour later, I now have several emails which triggers today's work. All will be replied to and work progressed by finishing time today, leaving me a clear head to go home knowing nothing is outstanding. If I find I have a few hours spare, I find work to do to get ahead of the game, I can draft and schedule some emails to be sent out at a later date (reminders etc), there is always some work I can do that's not yet due and with far away deadlines, so I can fill time by doing that. If all else fails, I can do some internal "housekeeping" such as archiving old files (paper and electronic), or updating internal manuals, etc.
There's the old saying "a clean desk is the sign of a clean mind" and it really is true, and applies to your home life too, and just as valid in this electronic world.