My recommendation is a small thing: a trashcan with a swinging lid!
Covers the trash, reduces smells, will prevent trash tetris (sometimes), and very good instead of foot-pedal opening trash cans or trash cans put in a cupboard.
Another thing are toothbrush holders that stick to mirrors. Might jog that memory of needing to brush your teeth!
Wall-mounted keyholder by your door, too. Anything I put on a flat surface will eventually be lost or covered with more junk & papers. My keys are WALL-ONLY!!!
What item(s) have helped you with your struggles?
Calendar on my phone. If a thing needs to happen it goes on the phone and a reminder is added for 15m to 1h before. Even things that don’t need to happen at a specific time, add it to the calendar so I can plan out the day.
1000000000000% Calendar is God. I remember everything all at once, and this lets me feel free to forget certain things.
Now I have a layer of “Did I add this to the Calendar” to deal with, it’s a trust issue with myself.