Your phone timer.

Ngl I find using an oven or microwave timer to be most effective, something external that I have to get up and go turn off forces me to deal with it immediately, phone alarms can be silenced and ignored lol

If you're on Android, I
Amdroid is great. Combination alarm clock/countdown timer, let's you save many different countdowns/alarms with names and alerting styles.

I use it all the time to make sure I don't forget shit. Washer and dryer each have a countdown for the length they run, along with dishwasher for the same reason.

I also use LifeUp to gamify my task list to help ensure I (generally) remember to do my daily/weekly tasks.

See, this is where shit like Amdroid comes in handy. Among the challenge (dismiss your alarm) options, they have NFC and QR/barcode as options. So you can force yourself to not be lazy by creating a tag, barcode or QR code that lives next to the thing you need to do by having to scan your verification to be able to shut your phone up.

I don't really have much advice on making you accountable to yourself, but the little things like this help force you to adult and not fuck up as much. Only thing that worked for me was to give myself a ton of anxiety so that overcoming my laziness/forgetfulness to prevent me from feeling the crippling anxiety from not getting shit done. 2/10, don't recommend.

Oh fuck yes. Only problem is remembering to add/update events. And with three adhd af people working off of a shared calendar.... Well, I'm just surprised we don't double book more often.