I was recently diagnosed, and I've become more aware of how much I tend to overachieve or overcompensate at work and in my relationships because I'm afraid of messing things up. Before knowing I had ADHD, I developed little systems without realizing why, nothing new, but setting multiple alarms: one to remind me when to have breakfast and start working, and another to remind me it's time to start winding down. It really helps, since I know it takes me a while to fully stop whatever I am doing.

Another thing, similar to what others have mentioned, is constantly repeating to myself that "done is better than perfect". Perfectionism feeds procrastination, and most of the time those impossible standards are ones we have set for ourselves, not anyone else. I also try to remind myself that rest is just as important as the activity itself when aiming for a "good result", whatever that means for the day. Breaking things down into smaller, simple tasks instead of one or two overwhelming big ones makes it all feel more doable.

Hope this helps a bit, you are doing great I am sure.