This might be the ADHD more than anything, but making alarms on my phone changed my life. I used to forget important things all the time, but then I started making alarms for the most important stuff, and all of a sudden I stopped forgetting them!

Nowadays I'll make an alarm for everything. I said I'd go get groceries after I finish this episode of my TV show? Better make an alarm for 7 minutes from now. I'm going to the store to buy eggs? Better make an alarm titled "eggs" to go off at the store in case I get distracted by something.

At this point I open my alarms app automatically any time there's anything at all to remember. I have dozens of concurrent alarms, and it's great.