Personally I'd like hear some of your experiences with different types of organizational software, no matter if it runs on a PC, phone or the cloud:
What are you using and in what ways does it help you with the troubles you are facing with your ADHD?
Do you use different tools for different use cases (e.g. one to organize and track bigger projects, one just for reminders or one as a knowledge base etc.)?
Is there any software you would specifically avoid and how so (e.g. cause it is distracting, pricey or you due to lack of data privacy)?
Or is there things you'd really recommend to try out, because it helped you immensely in a way?
To start it off: Personally I got diagnosed as an adult rather recently. I somehow have haphazardly kept my life together without meds and ADHD-Therapy/Counseling/Coaching so far, but got no idea how.
I made use of all sorts of organization methods and tools without it ever occurring to me that I could have ADHD.
Looking back it became painfully clear, I never consciously took my brain being different into account at any point. Therefore I failed very often and very spectacularly with my organization. I still do, especially at work.
Personally I use synched calendars (Thunderbird & Fairmail synched over Nextcloud) on my phone and PC at the moment.
I also found I use ToDoList-Apps a lot (currently TickTick) to put at least some structure to my chaos. I am really awful with reminders though: I have too many and not enough at the same time. There is no structure to the types of reminders I have and I geht them from too many different sources. And sometimes they are too distracting or worse yet, sometimes not noticeable enough (Looking at you there, Outlook).
I have found no software solution, premade or coded by myself personally, that beats a pen & paper bullet journal.
I recently tried one that boasted about how it used AI to help organize your tasks, but it didn't and couldn't do the one thing I needed it to, which is automatically populate a daily to-do list with suggested tasks.
May I ask how you manage everything that is expected from you at the moment? Like another poster wrote, if I am in a ditch, pen and paper are always reliable.
But I am also familiar with the tried and true system of just seeing where your brain takes you. Not always great places imo, but over half of my life I did just that.
In a familiar situation (at work, getting my kids ready for school) I just look around for all the things I can see need doing and do whatever is highest priority.
In an unfamiliar situation (eg. trying to schedule back-to-school checkups) I flounder. I still look around for all the things I can see need doing, but;
I don't always know what needs doing
I don't always know how to do it
I tend to do not the highest-priority task but the one with the lowest cost / barrier-to-entry
I will be fighting my anxiety, related to the first two points, the whole time